Geometry Selected Answers 1
Geometry Selected Answers 1
                                                                                                                                                                        11.                                                                             17.
                   Evaluate
                       1. line segment; defined term
                       3. ray; defined term
                       5.
                                                                                                                                                                        Evaluate
                       9. AB z BC, so AB and BC do not have the                                                                                                             1.
                          same length.                                                                                                                                                                                                                  19.
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                                                                                                                                                                                               Selected Answers
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Selected Answers
                   25. A. No
                        B. Yes
                                                                                                                                                                        UNIT 1 Selected Answers
                        C. Yes                                                                                                                                          
                                                                                                                                                                        MODULE 1                                                                        Evaluate
                        D. No
                                                                                                                                                                                                                                                          1.
                        E. No                                                                                                                                           Lesson 1.3 Representing and
                   27. Yes; the construction still works. In this                                                                                                       Describing Transformations
                       case, the construction produces two right
                       angles since each has half the measure of                                                                                                        Your Turn
                       a straight angle (180q).                                                                                                                             5. The transformation is a rotation of 180q
                                                                                                                                                                               around the origin (x, y) o (x, y).
                                                                                                                                                                              DE       DcEc      6               mD          mDc         90q
                                                                                                                                                                              EF      EcFc           45          mE          mEc         27q                 rotation of 180q around the origin
                                                                                                                                                                              DF      DcFc       3               mF         mFc         63q             3.
                                                                                                                                                                              The transformation preserves length and
                                                                                                                                                                              angle measure.
                                                                                                                                                                            6. The transformation is a translation
                   29. Construct the bisector of the given angle.                                                                                                              (x, y) o (x  1, y  2).
                       Then construct the bisector of one of the
                       angles that was formed.                                                                                                                                ST      ScTc       5               mS          mSc         76q
                                                                                                                                                                              TU      TcUc           32          mT         mTc         45q
                                                                                                                                                                              SU       ScUc          17          mU          mUc         59q
 SA2
                                                                                                                                                                                                                                                                                                                       1
                                                                                                                                                                                                                                                               vertical compression by a factor of
                                                                                                                                                                              The transformation preserves length and                                                                                                  3
                                                                                                                                                                              angle measure.
                                                                                                                                                                                                                                                          5. (x, y) o (y, x); rotation of 90q clockwise
                                                                                                                                                                            8. (x, y) o (1.5x, 1.5y)                                                         around the origin.
                                                                                                                                                                              AB      2                                                                        The transformation preserves length and
                                                                                                                                                                              AcBc      3                                                                      angle measure.
                                                                                                                                                                              Since AB z AcBc, the transformation is not                                              §1 1 ·
                                                                                                                                                                                                                                                          7. (x, y) o ¨ x, y ¸
                                                                                                                                                                              a rigid motion.                                                                         ©2 2 ¹
                                                                                                                                                                                        §1       ·                                                             Since AB z AcBc, the transformation is not
                                                                                                                                                                            9. (x, y) o ¨ x, 3 y ¸
                                                                                                                                                                                        ©2       ¹                                                             a rigid motion.
                                                                                                                                                                                                                                                          9.
                                                                                                                                                                              RS          37
                                                                                                                                                                              RcSc          18
                                                                                                                                                                              Since RS z RcSc, the transformation is not
                                                                                                                                                                              a rigid motion.
(x, y) o (1.5x, y)
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                                                                                               3                                                                                                                                                    4
                                                                                                                                                                               three numbers.
                                                                                                                                                                            3. The conclusion is based on two
                                                                                                                                                                               observations.
                                                                                                                                                                            5. Counterexample 2; if x 2, then x  1                          3,
                                                                                                                                                                               which is a prime number.
                                                                                                                                                                            7. When I draw three points that are
                                                                                                                                                                               noncollinear, I can draw a single plane
                                                                                                                                                                               through all three points, so they are
                                                                                                                                                                               coplanar after all.
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                                                                                                                                                                                               Selected Answers
                                                                                                                                                                                               Selected Answers
Selected Answers
5.
                                                                                                        JJJK
 SA4
9. GH , 5, 2
                                                                                                   19. 4, 6
                                                                                                   21. (0, 2); (1, 3); (2, 2); (1, 1); Possible
                                                                                                       answer I used a table to find the
                                                                                                       coordinates of the second polygon. Then I
                                                                                                       made a new table, using the coordinates
                                                                                                       from the second polygon to find the                                       Ac(2, 4), Bc(1, 1), Cc(4, 1)
                                                                                                       coordinates of the third polygon.
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                                                                                               7                                                                                                                                                    8
5. 15.
5.
                                                                                                   17. (0, 2)
                       7.
                                                                                                   19. JM         14
                                                                                                   21. When the tab key is pressed twice, the                                                                                                             5.
                                                                                                       logo is reflected into Quadrant III and then
                                                                                                       reflected back to its original position in
 SA5
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                                                                                                                                                                                               Selected Answers
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Selected Answers
                   15.
                                                                                                                                                                        UNIT 1 Selected Answers
                                                                                                                                                                        
                                                                                                                                                                        MODULE 2
                                                                                                                                                                        Lesson 2.4 Investigating
                                                                                                                                                                        Symmetry
                                                                                                                                                                        Your Turn
                         M (4, 2)                                                                                                                                          6. line, rotational
                                                                                                                                                                               4
                         N (1, 2)                                                                                                                                             90q, 180q, 270q
                         P (1, 4)                                                                                                                                          7. line
                   17. 18q                                                                                                                                                     1
                                                                                                                                                                               none
                   19. Possible answer Starting with triangle 1,
                       rotate clockwise 60º around the vertex at                                                                                                            8. rotational
                       the center of the hexagon. Repeat the                                                                                                                   0
                       process using each successive image as                                                                                                                  72q, 144q, 216q and 288q
                       a preimage.                                                                                                                                          9. none
                   21. a. False                                                                                                                                                0
                                                                                                                                                                               none
                         b. True
                         c. True                                                                                                                                        Evaluate
                                                     +
 SA6
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                                                                                              11                                                                                                                                                   12
                                                                                                                                                                         5.                                                                               9. B
                   UNIT 1 Selected Answers                                                                                                                                                                                                              11. F
                                                                                                                                                                                                                                                       13. sometimes
                   MODULE 3                                                                        13. The reflection across the y-axis will move
                                                                                                                                                                                                                                                        15. sometimes
                                                                                                       the rectangle from the right of the y-axis to
                   Lesson 3.1 Sequences of                                                             the left of it. Due to the symmetry of the                                                                                                       17. sometimes
                                                                                                       rectangle, it will appear to have been                                                                                                           19. a. Yes
                   Transformations                                                                     translated left 6 units. Then, translating
                                                                                                                                                                                                                                                              b. Yes
                   Your Turn                                                                           along the vector ۃ5, 4 ۄwill move the
                                                                                                       rectangle right 5 units and up 4 units.                                                                                                                c. No
                       7.                                                                              This will bring the rectangle fully into                                                                                                               d. Yes
                                                                                                       Quadrant I. The final result will be a
                                                                                                       rectangle that is the same shape and size
                                                                                                                                                                                                                                                        21. Possible answer Reflect ABC across        +
                                                                                                                                                                                                                                                            the y-axis and then translate it down 7
                                                                                                       as the preimage that has moved to sit on
                                                                                                                                                                                                                                                            units.
                                                                                                       the x-axis in Quadrant I, closer to the
                                                                                                       y-axis than the preimage.                                                                                                                              (x, y) o (x, y  7)
                                                                                                   14. A horizontal stretch will pull points U and                       7.
                                                                                                                                                                                                                                                        23. The order of these two reflections does
                       8.                                                                              T away from the y-axis, making the                                                                                                                   not matter. The resulting image is the
                                                                                                       triangle longer in the left-to-right direction.                                                                                                      same for a reflection in the y-axis followed
                                                                                                       The translation along the vector ۃ2, 1 ۄwill                                                                                                         by a reflection in the x-axis as for a
                                                                                                       move the stretched triangle 2 units right                                                                                                            reflection in the x-axis followed by a
                                                                                                       and 1 unit up, which will move the triangle                                                                                                          reflection in the y-axis.
                                                                                                       closer to the origin with one vertex on the
                                                                                                       x-axis and another across the y-axis. The
                                                                                                       final image will not be the same shape or
                                                                                                       size as the preimage.
                   11.
 SA7
                                                                                                   Evaluate
                                                                                                     1.
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                                                                                                                                                                                               Selected Answers
                                                                                                                                                                                               Selected Answers
Selected Answers
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Selected Answers
                       9. m10        69q
                   11. m7          118q
                   13. m14           66q
                   15. y      40                                                                                                                                            8. Same side interior angles; by the
                                                                                                                                                                               Converse of the Same Side Interior
                         x    15
                                                                                                                                                                               Angles Postulate.
                   17. y      15
                                                                                                                                                                            9. Corresponding angles; by the Converse of
                   19.                                                                                                                                                         the Corresponding Angles Theorem.
                             Statements                          Reasons                                                                                                15.
                         1. p q                       1. Given                                                                                                                                       Statements                                                               Reasons
                         2. m3         m5           2. Alternate Interior                                                                                                      1. lines A and m are cut by a transversal;
                                                                                                                                                                                                                                                   1. Given
                                                         Angles Theorem                                                                                                            1 # 2
                         3. m1         m3           3. Vertical Angles                                                                                                         2. m1      m2                                                   2. Definition of congruence
                                                         Theorem
                                                                                                                                                                                 3. 2 and 3 are supplementary.                                   3. Linear Pair Theorem
                         4. m1         m5           4. Substitution
                                                                                                                                                                                 4. m2  m3            180q                                      4. Definition of supplementary angles
                                                         Property of Equality
                                                                                                                                                                                 5. m1  m3            180q                                      5. Substitution Property of Equality
                                                                                                                                                                                 6. 1 and 3 are supplementary.                                   6. Definition of supplementary angles
                                                                                                                                                                                                                                                   7. Converse of Same-Side Interior
                                                                                                                                                                                 7. A & m
                                                                                                                                                                                                                                                      Angles Postulate
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                                                                                              19                                                                                                                                                   20
                   11. 90q
                                                                                                                                                                            7. y     5x  3
                   13. 180q
                                                                                                                                                                            9. y     3x  36
                   15. x        45; y     5.
                                                                                                                                                                                                                3
                   17. The valve pistons are lines that are                                                                                                             11. The top line slope is                 . The bottom line
                                                                                                                                                                                                                4
                       perpendicular to the same line (the lead
                                                                                                                                                                                         2
                       pipe), so they form right angles with the                                                                                                                 slope is  . The lines do not have the
                       same line. By the corresponding angles                                                                                                                            3
                       theorem, all the congruent right angles                                                                                                                   same slope, so they are not parallel.
                       mean the valve pistons are parallel to                                                                                                                           1    1
                       each other.                                                                                                                                      13. y             x
                                                                                                                                                                                        2    2
                   19. are both obtuse                                                                                                                                  15. y        2x  17
                         90q                                                                                                                                            17. a. y            x  30
                         the definition of obtuse angles
                                                                                                                                                                                 b. y       x  30
                         180q                                                                                                                                                    c. They are perpendicular.
                         m1  m2              180q
                         false
                         1 and 2 cannot both be obtuse
Selected Answers
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                                                                                                                                                                                               Selected Answers
Selected Answers
                   Evaluate                                                                                                                                                         +
                                                                                                                                                                                 4.  JML #  KLM+               4. ASA Triangle Congruence Theorem
                       1. Possible answer counterclockwise                                                                                                                 9.
                          rotation about point M by mQMN                                                                                                                                    Statements                                                   Reasons
                                                          HJJJG
                          followed by a reflection across MQ.                                                                                                                    1. S and U are right angles. 1. Given
                         +               +
 SA12
                       3.  ABC #  DEF because all six pairs of                                                                                                                 2. S # U                                        2. All right angles are congruent.
                          corresponding parts are congruent.
                                                                                                                                                                                 3. RV bisects SU                                  3. Given
                       5. JK z MN. Not congruent; there aren’t six
                          pairs of congruent corresponding parts.                                                                                                                4. ST # UT                                        4. Definition of bisector
                       7. z   1.6                                                                                                                                                5. RTS # VTU                                    5. Vertical angles are congruent.
                       9. w    27                                                                                                                                                   +
                                                                                                                                                                                 6.  RST #  VUT +                                6. ASA Triangle Congruence Theorem
                   11. LM is not congruent to QR. So, the                                                                                                               Evaluate
                       triangles are not congruent.
                   13. The triangles have six pairs of congruent                                                                                                            1. a.
                       corresponding parts, and are congruent
                       by the converse of CPCTC.
                   15. 7       x
                         y    37
                   17. Never true
                                                                                                                                                                                 b. Yes; the triangles are congruent by ASA. Therefore, there is a sequence of rigid motions
                   19. Sometimes true                                                                                                                                               that will map my triangle onto Natasha’s triangle.
                   21. a. Not congruent
                                                                                                                                                                                 +           +
                                                                                                                                                                            3.  JKL #  MNP by ASA.
                         b. Congruent
                         c. Congruent
                                                                                                                                                                                                                +
                                                                                                                                                                            5. None of the angles in  STU has a measure of 34q. So,                                  +STU is not congruent to +PQR.
                                                                                                                                                                            7. Given
                         d. Not congruent
                                                                                                                                                                                 CBA # DBA
                         e. Congruent
                                                                                                                                                                                 AB # AB
                   23. No; LN # LN by the Reflexive Property of
                                                                                                                                                                                 ASA Triangle Congruence Theorem
                       Congruence. Therefore, the triangles are
                       congruent.
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                   15.
                                            Statements                                                        Reasons
                         1. A # E                                                   1. Given
                         2. C is the midpoint of AE.                                  2. Given
                         3. AC # EC                                                   3. Definition of midpoint
                         4. ACB # ECD                                               4. Vertical angles are congruent.
                             +
                         5.  ACB #  ECD    +                                        5. ASA Triangle Congruence Theorem
                         6. AB # ED                                                   6. CPCTC
                   17. In each sign, the side that is 36 in. long is the included side between two 60q angles.
                       Therefore, by the ASA Triangle Congruence Theorem, the signs are congruent.
                   19. B and D are both right angles, so B # D; CB CD, so CB # CD; ACB and ECD
                       are vertical angles, so ACB # ECD. Therefore,  ACB #     ECD by the ASA Triangle +               +
                       Congruence Theorem. Since corresponding parts of congruent triangles are congruent,
                        AB # ED, so AB ED. Mariela can find the distance AB across the canyon by measuring
                       the distance ED.
Selected Answers
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                                                                                                                                                                                               Selected Answers
                                                                                                                                                                                              Selected Answers
Selected Answers
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Selected Answers
                                                                                                                                                                                          4  0 
                                                                                                                                                                                                      2
                   UNIT 2 Selected Answers                                                                                                                                    BC                           (1  3)2         20,
                                                                                                                                                                             and EF            4  0
                                                                                                                                                                                                           2
                                                                                                                                                                                                                ( 2  0)   2
                                                                                                                                                                                                                                    20.
                   MODULE 6
                                                                                                                                                                             Therefore, AB # DE and BC # EF . By the Slope Formula,
                   Lesson 6.3 HL Triangle Congruence
                                                                                                                                                                                                      34             1                               1 4
                                                                                                                                                                             slope of AB                              , slope of AC                                   3,
                   Your Turn                                                                                                                                                                         0  ( 3)        3                             4  ( 3)
                                  +                        +
                       3. Yes. VWX and YXW are right triangles that share hypotenuse WX < WX # WX by the                                                                                             0  ( 3)                                     2  ( 3)        1
                          Reflexive Property of Congruence. It is given that WV # XY , therefore VWX # YXW                                 +                +                slope of DE
                                                                                                                                                                                                       0 1
                                                                                                                                                                                                                      3, slope of DF
                                                                                                                                                                                                                                                     4 1            3
                                                                                                                                                                                                                                                                       .
                          by the HL Triangle Congruence Theorem.
                       5. It is given that and  CAB and  DBA are right angles and AD # BC. AB # AB by the
                                                                                                                                                                                                 
                                                                                                                                                                             Since slope of AB < slope of AC                               1, AB A AC and A is a right angle.
                                                                                                    1. Given
                                                                                                                                                                            and a leg of the first right triangle are congruent to the hypotenuse and a leg of the second
                            2. H is the midpoint of GK.                                             2. Given                                                                right triangle, so the triangles are congruent by the HL Triangle Congruence Theorem.
                            3. GH # HK                                                              3. Definition of midpoint                                           23. There is an LL Triangle Congruence Theorem.
                              +
                            5.  FGH #  JHK +                                                      5. HL Triangle Congruence Theorem                                        1. A and D are right angles.                                              1. Given
                                        0  ( 3)
                                                       2
                            AB                              (3  4)2      10,
                                       1  0 
                                                  2
                            DE                         ( 3  0)2      10,
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                                                                                                                                                                                                    Selected Answers
                                                                                                                                                                                               Selected Answers
Selected Answers
                       5. No                                                                       29. Write two equations, AD2  CD2                            AC 2                                                                                          Let the three towns be vertices of a
                       7. Yes                                                                                                                                                                                                                                  triangle. By the Circumcenter Theorem,
                                                                                                         and BD  CD  2          2         2
                                                                                                                                      BC . Equating                         9.
                                                                                                                                                                                                                                                               the circumcenter of the triangle is
                       9. 5  x  11                                                                     expressions for CD 2 , AC 2  AD2                                                                                                                     equidistant from the vertices. Trace the
                   11. 5.3  x  49.9                                                                       BC 2  BD2 and therefore
                                                                                                                                                                                                                                                               outline of the lake. Draw the triangle
                                                                                                                                                                                                                                                               formed by the towns. To find the
                   13. m A, m B, m C                                                                   AC 2  BC 2 AD2  BD2 . Since the right                                                                                                              circumcenter, find the perpendicular
                   15. m P, m R, m Q                                                                  side is positive, so is the left side, which                                                                                                          bisectors of each side. The position
                                                                                                         leads to BC  AC.                                                                                                                                     of the boat is the circumcenter, F.
                   17. DE, EF, DF
                                                                                                                                                                                                                                                        15. a. To find AB, note that DB is a leg of
                   19. PR, PQ, QR
                                                                                                                                                                                                                                                                                       +
                                                                                                                                                                                                                                                               right triangle ZBD and ZB is the
                                                                                                                                                                                  3.5, 4                                                                     hypotenuse. Use the Pythagorean
                                                                                                                                                                                                                                                               Theorem to find DB and multiply by 2
                                                                                                                                                                        Evaluate
                                                                                                                                                                                                                                                               because D is the midpoint of AB . To
                                                                                                                                                                            1.                                                                                 find AC, use the same method, noting
                                                                                                                                                                                                                                                               first that ZC ZB because C is the
                                                                                                                                                                                                                                                               circumcenter of ABC. Also, ZF is a
                                                                                                                                                                                                                                                                                                 +
                                                                                                                                                                                                                                                               leg of right triangle ZCF and ZC is
                                                                                                                                                                                                                                                               the hypotenuse.
                                                                                                                                                                                                                                                               b. AB        210; AC         288
                                                                                                                                                                                                                                                               c. No; the only information given about
                                                                                                                                                                                                                                                                                  +
                                                                                                                                                                                                                                                                  isosceles ZBC is the length of two
                                                                                                                                                                                                                                                                  sides, which is insufficient for finding BC
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                                                                                              35                                                                                                                                                   36
                                                                                                       made a circle that just touches the three                            3. No; no matter how you change the shape                                       horizontal line. The orthocenter remains
                                                                                                       sides of the triangle.                                                     +
                                                                                                                                                                               of  ABC, the point at which the medians                                     at C, the origin.
                                                                                                                                                                               intersect is always in the interior of the
                                                                                                                                                                               triangle.
                                                                                                                                                                            5. 24 FH;
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                                                                                                                                                                                              Selected Answers
                                                                                                                                                                                               Selected Answers
Selected Answers
                   slopes are the same, UW & YZ.                                                   21. Possible answer: First construct a triangle                                                                  DB # DB
                                                                                                       with a straightedge. Next use the                                      ABD # CDB;                                                                    5. Isosceles Triangle Theorem
                                                                          1
                   UW           26; YZ         2 26; So UW
                                                                          2
                                                                            YZ.                        compass to find the midpoint of two sides
                                                                                                       of the triangle. Finally, connect the two
                                                                                                                                                                              +ABD # +CDB                                                                     6. Transitive Property of Congruence
                       6. JL     78; PM          47.5; mMLK               105q                        midpoints to create a midsegment parallel                               AB # CB and AD # CB                                                      17. Sometimes; opposite sides of a
                                                                                                       to the third side.                                                                                                                                   parallelogram are congruent, but
                   Evaluate
                       1. Drawings will vary. Students should
                                                                                                   23.   +QXY # +XPZ # +YZR # +ZYX;                                       5. 1. ABCD is a parallelogram                                                   consecutive sides, such as RS and ST ,
                                                                                                                                                                                                                                                            may or may not be congruent.
                                                                                                                                                                              2. AB || DC
                                                                                                         area of +XYZ #   area of +PQR
                                                                                                                        1
                          conclude that the midsegment is half the                                                                                                                                                                                      19. Always; opposite sides of a parallelogram
                          length of the third side.                                                                     4                                                     3. ABE # CDE, BAE # DCE
                                                                                                                                                                                                                                                            are congruent.
                       3. The slope of XY and GH is undefined,                                                                                                                4. AB # DC                                                                21. Never; diagonals of a parallelogram bisect
                          so the lines are parallel. The length of                                                                                                            5.   +ABE # +CDE                                                              each other.
                           XY is 3 and the length of GH is 6, so                                                                                                                                                                                        23. a. 3, 6, 8;
                                1                                                                                                                                             6. AE # CE and BE # DE
                          XY       GH.                                                                                                                                                                                                                        b. 1 is supplementary to 2, 4,
                                2                                                                                                                                             1. Given                                                                           5, and 7.
                                                                                                                                                                              2. Definition of parallelogram                                            25. The side lengths of the tile are 6 inches
                                                                                                                                                                              3. Alt. Int. Angles Thm.                                                      and 8.5 inches.
                                                                                                                                                                              4. Opposite sides of a parallelogram are                                  27. y       2x
                                                                                                                                                                                 congruent
                                                                                                                                                                              5. ASA Triangle Cong. Thm.
                                                                                                                                                                              6. CPCTC
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                                                                                              39                                                                                                                                                   40
UNIT 3 Selected Answers 17. 1. Draw DB 21. Possible answer: When you draw AC,
                                                                                                                                                                            2. AB # CD                                                                                      +
                                                                                                                                                                                                                                                            you form DAC and BAC. LM is a        +
                   MODULE 9                                                                          3. Possible answer: It is given that                                    3. AB || CD
                                                                                                                                                                                                                                                                                       +
                                                                                                                                                                                                                                                            midsegment of DAC, so LM || AC and
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                                                                                              41                                                                                                                                                   42
                                                                                                                                                                                               Selected Answers
                                                                                                                                                                                              Selected Answers
Selected Answers
                                                                                                                                                                                                           1
                                                                                                                                                                              slope of NK              
                                                                                                                                                                                                           2
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                                                                                              45                                                                                                                                                   46
                                                                                                                                                                                               Selected Answers
                                                                                                                                                                                               Selected Answers
Selected Answers
                                                                       3  ( 3)
                   25. The slope of QP should be                                       2 .                                                                             UNIT 3 Selected Answers
                                                                        03
                                                          1                                                                                                             
                        The slope of QR                   and the slope of
                                                          3                                                                                                             MODULE 10                                                                                                       42              2
                                                                                                                                                                                                                                                          7. slope of KL                                   ;
                             3                                                                                                                                                                                                                                                        1   4         3
                        RS     . No sides of PQRS are parallel,                                                                                                         Lesson 10.2 Slope and
                             2                                                                                                                                                                                                                                                          1                               2
                        so PQRS is not a trapezoid.                                                                                                                     Perpendicular Lines                                                                   slope of LM               ; slope of MN                    ;
                                                                                                                                                                                                                                                                                        4                               3
                   27. Possible answer Plot the points A(4, 2),                                                                                                       Your Turn                                                                             slope of NK 3; A pair of opposite sides
                       B(2, 4), C(4, 0), D(0, 2).                                                                                                                                                                                                            do not have the same slope, so these
                                                                                                                                                                                                           2
                        midpoint of AB M(1, 3); midpoint                                                                                                                   5. slope of DE                                                                   sides are not parallel. Therefore, KLMN is
                                                                                                                                                                                                           3
                        of BC N(3, 2); midpoint of CD                                                                                                                                                                                                         not a parallelogram.
                                                                                                                                                                                                      3
                        P(2, 1); midpoint of DA Q(2, 0);                                                                                                                    slope of EF                                                                 9. Always
                                                    JJJG                                                                                                                                              2
                                          1                                                                                                                                                                                                             11. Never
                        slope of MN  ; slope of NP 3;                                                                                                                                                     2
                                         4                                                                                                                                    slope of FG                                                             13. Never
                                         1                                                                                                                                                                 3
                        slope of PQ     ; slope of QM 3.                                                                                                                                                                                               15. PQ         RS       10.5 and QR              SP         31.5
                                         4                                                                                                                                                     3
                                                                                                                                                                              slope of GD                                                               17. PQ         RS       6 and QR            SP         36
                        Since opposite sides are parallel, MNPQ                                                                                                                                2
                                                                                                                                                                                                                                                                     1
                        is a parallelogram. This is true when                                                                                                                 Consecutive sides are perpendicular since                                 19. y        x2
                        starting with any set of four points.                                                                                                                 the product of the slopes is 1.                                                       2
                        Conjecture The quadrilateral formed by                                                                                                               Quadrilateral DEFG is a rectangle                                         21. The coordinates of C are (0, 4).
                        connecting the midpoints of consecutive                                                                                                               because it is a quadrilateral with four right                                   The coordinates of D are (4, 2).
 SA24
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                                                                                              47                                                                                                                                                   48
                                                                                                                                                                                                        0  3a         0  b 
                                                                                                                                                                                                                    2                2
                   UNIT 3 Selected Answers                                                                                                                                         and NB                                                       9a 2  b 2 ,        15. The distance between the ships is
                                     +
                         area of DBC 16 units2                                                           Y¨
                                                                                                          ©    2
                                                                                                                   ,
                                                                                                                      2 ¸¹
                                                                                                                             Y (3a, b ) ,                                         coordinates of V are
                                                                                                                                                                                     § 3   1 6   2  ·
                                            +
                         The area of DBC is one half the area of                                                                                                                  V ¨¨                       ¸¸ V(1, 4).
                         +
                                                                                                                                                                                                ,
                           ABC.                                                                            § 0  4a 0  0 ·                                                          ©    2          2        ¹
                                                                                                          Z¨       ,
                                                                                                                      2 ¸¹
                                                                                                                                          Z (2a, 0)
                   10. By the Distance Formula, AB     17 ,
                                                                                                           © 2
                                                                                                                                                                                   JK          32 , KV            20 , JV                68 ,
                       BC     5 , AC    34 , DE    17 ,                                                  By the Distance Formula,
                                                                                                                                                                                   PQ           32 , QU             20 , PU               68 .
                         EF         5 , DF           34 . So, AB # DE ,                                   XZ          2a  a   0  b 
                                                                                                                                2                 2
                                                                                                                                                            a b
                                                                                                                                                             2     2
                                                                                                                                                                        and
                                                                                                                                                                                   So, JK # PQ , KV # QU , and JV # PU .
                         BC # EF , and AC # DF . Therefore,
                         +ABC # +DEF         by the SSS Triangle
                                                                                                         YZ          2a  3a    0  b 
                                                                                                                                    2                 2
                                                                                                                                                            a2  b2 .                                 +
                                                                                                                                                                                   Therefore, JKV # PQU by the SSS      +
                         Congruence Theorem and BCA # EFD                                              Since XZ YZ, XZ # YZ and                            + XYZ is              Triangle Congruence Theorem and
                                                                                                                                                                                   KVJ # QUP since corresponding parts
                         since corresponding parts of congruent                                          isosceles.                                                                of congruent triangles are congruent.
                         triangles are congruent.
                                                                                                     5. Assign coordinates as shown in the figure.
                   11. By the Midpoint Formula, the coordinates                                                                                                               13. JK          17, KL            34, and JL                  17.
                                                                                                        By the Midpoint Formula, the coordinates
                                    § 3  ( 1) 5  ( 1) ·                                            of M and N are as follows.                                                 Since JK and JL have the same length,
                       of M are M ¨             ,
                                    ©     2         2 ¸¹                                                   § 0  2a 0  2b ·                                                        JK # JL , and therefore the triangle is
                                                                                                         M ¨       ,                        M  a, b  ;
                       M (2, 2) and the coordinates of N are                                              © 2         2 ¸¹                                                        isosceles.
                          § 4  2 5  ( 1) ·
                       N ¨       ,                                                                         § 2a  4a 2b  0 ·
                                      2 ¸¹
                                                N (3, 2).
                          © 2                                                                            N ¨        ,                         N  3a, b 
                                                                                                           ©    2      2 ¸¹
                         By the Distance Formula, PQ                           40 ,
                                                                                                         By the Distance Formula,
Selected Answers
                         QN       5, PN           45 , RS             40 , SM         5,
                                                                                                                       4a  a          0  b 
                                                                                                                                    2                 2
                                                                                                         MC                                                 9a 2  b 2
                         RM          45.
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                                                                                                                                                                                                     Selected Answers
                                                                                                                                                                                                 Selected Answers
Selected Answers
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                                                                                                                                                                                 1 to 3.
                                                                                                                                                                        Evaluate
                                                                                                                                                                            1. The ratios of the lengths of the
                                                                                                                                                                               corresponding sides are equal.
                                                                                                                                                                            3. No, this is not a dilation.
                                                                                                                                                                            5. (c)
                         P | 10.2 units
                                             2
                                                                                                                                                                            7.
                         A     4.5 units
                   17. JK           18       3 2 ; KL             45       3 5;
                         LM          45       3 5 ; JM              18       3 2
                         So JK # JM # KL # LM , and therefore
                         JKLM is a kite.                                                                                                                                                                                                                      a. Perimeter is 12 units, Area is 6 square
                         A     27 units2                                                                                                                                                                                                                         units
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53 54
                                                                                                                                                                                               Selected Answers
                                                                                                                                                                                               Selected Answers
Selected Answers
                                                                                                                                                                                                      +
                                            §1 1 ·                                                       Step B Translate AcBcCcDc with
                                                                                                                                       JJJJG a
                         Dilation (x, y) o ¨ x , y ¸                                                                                                                        Step B Rotate DXC 180q around point
                                            ©3 3 ¹                                                       translation along the vector AcE, producing
                                                                                                         AsBsCsDs. Through this translation, As is                           X so that DXC coincides with AXB.
                       9. Rotation (x, y) o (x, y)
                                                                                                         mapped to E. It may be true that Bs is
                                                                                                                                                                             Step C Dilate DXC by a factor of k about
                                            §3 3 ·                                                       mapped to F, Cs is mapped to G, and Ds
                         Dilation (x, y) o ¨ x, y ¸                                                                                                                         the center X. This dilation moves the point
                                            ©2 2 ¹                                                       is mapped to H. If not, rotate AsBsCsDs
                                                                                                                                                                             D to A, since k(DX) AX, and moves C to
                                                                                                         about E so that Bccc is mapped to F.
                         Translation (x, y) (x  3, y  1.5)                                                                                                                B, since k(CX) BX. Since the dilation is
                                                                                                         Then, C ccc lands on G and Dccc lands on H.                         through point X and dilations take line
                   10. Translate JKLMN right 7 units so that                                       13. Step A Dilate            +ABC with center of                         segments to line segments, DXC is             +
 SA28
                       J maps to V.
                                             HJJG                                                                                          x                                                    +
                                                                                                                                                                             mapped to AXB. So DXC is similar to  +
                       Reflect JKLMN across JN.
                                                                                                         dilation B and scale factor K
                                                                                                                                           a
                                                                                                                                             , producing
                                                                                                                                                                              + AXB.
                         Dilate JKLMN with center J and scale                                            +                                           +
                                                                                                            AcB cC c. After the dilation AcB cC c will
                                                                                                                                               x                        23. Step A Draw the bisector of AXC.
                                1                                                                        have sides of length B cC c ka          (a ) x,
                         factor .
                                2
                                                                                                                        x        bx
                                                                                                                                               a
                                                                                                                                                                                                       +
                                                                                                                                                                             Step B Reflect CXD across the angle
                                                                                                         A cC c kb        (b )       , and                                   bisector. This maps XC to XA. Since
                   Evaluate                                                                                             a         a
                                                                                                                        x       cx                                           reflections preserve angles, it also maps
                       1. EFGH can be mapped onto ABCD with
                          a dilation of 4 with center at the origin.
                                                                                                         A cB c kc
                                                                                                                        a
                                                                                                                          (c )
                                                                                                                                 a
                                                                                                                                    . These are the                           XD onto XB. Since XCD # XAB,     +               +
                                                                                                         same side lengths of XYZ. By SSS   +                                the image of CD is parallel to AB.
                       3. JKLMN is similar to JPQRS.
                                                                                                         Triangle Congruence, AcB cC c is   +
                       5. Reflection (x, y) o (x, y)
                                                                                                         congruent to XYZ.     +                                             Step C Dilate          +
                                                                                                                                                                                               XCD about point XHJJG
                                                                                                                                                                                                                 . This
                         Translation (x, y) o (x, y 6)
                                                                                                                                      +
                                                                                                         Step B Translate AcB cC c along the
                                                                                                                  JJJJG
                                                                                                                                                                             moves the HJJG
                                                                                                                                                                                         new point C to A. Since AB is
                                                                                                                                                                                                      HJJG          HJJG
                       7. Reflection (x, y) o (x, y)                                                                                        +
                                                                                                         vector BcY, producing AccB ccC cc. Through
                                                                                                                                                                             parallel to CD, the new CD, moves to AB .
                                                                                                                                                                             Therefore, the new point D is mapped to B
                                            §1 1 ·
                         Dilation (x, y) o ¨ x, y ¸
                                                                                                         this translation, Bs is mapped to Y. It may                         and     +
                                                                                                                                                                                     XCD is mapped to XAB. So           +
                                            ©2 2 ¹                                                       be true that As and Cs are mapped to X
                                                                                                                                         +
                                                                                                         and Z. If not, rotate AccB ccC cc about Y so
                                                                                                                                                                              +XCD is similar to XAB.         +
                       9. Reflection (x, y) o (x, y)
                                                                                                         that Bccc is mapped to Y. Then, Cccc is
                         Dilation (x, y) o (3x, 3y)                                                     mapped to Z.
                         Translation (x, y) o (x  1, y  2)
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                                                                                              55                                                                                                                                                   56
                                                                                                                                                                            1.             or 1.5                                                                            XY           XZ
                                                                                                                                                                                  3      2                                                                  AcCc k < AC          < AC        < AC XZ.
                   11. XZ           42                                                                                                                                                                                                                                       AB          AC
                   13. YZ           n2  4n  4                                                                                                                                  2.1    3
                                                                                                                                                                                          or 1.5                                                                                +
                                                                                                                                                                                                                                                              Therefore, AcBcC # XYZ by SAS      +
                                                                                                                                                                                 1.4    2                                                                     Congruence. So a sequence of rigid
                   15. x
                   17. a
                                7
                                 2; b    3                                                                                                                                       3.9     3
                                                                                                                                                                                           or 1.5
                                                                                                                                                                                                                                                                                      +
                                                                                                                                                                                                                                                              motions maps AcBcC to XYZ. The            +
                                                                                                                                                                                 2.6     2                                                                    dilation followed by this sequence of rigid
                   19. Yes, corresponding angles are congruent.                                                                                                                                                                                               motions shows that there is a sequence
                       The ratio of corresponding sides is                                                                                                                  3. By the AA Triangle Similarity
                       constant.                                                                                                                                                        +      +
                                                                                                                                                                               Theorem, ABC a DEF.
                                                                                                                                                                                                                                                              of similarity transformations that maps
                                                                                                                                                                                                                                                              +                +
                                                                                                                                                                                                                                                                 ABC to XYZ. So ABC a XYZ.       +               +
                   21. x o 48x                                                                                                                                              5.   +ABC a +EDC by the AA Triangle                                         21. Possible Answer For XB to be as small
                   23. Possible answer (x, y) o (2x, 2y) o                                                                                                                      Similarity Theorem.
                       (x  14, y  8) or (x, y) o (x  7, y  4) o                                                                                                                                                                                         as possible, it should correspond to the
                       (2x, 2y)
                                                                                                                                                                            7. The triangles are similar by the AA
                                                                                                                                                                               Triangle Similarity Theorem. It is not
                                                                                                                                                                                                                                                                                        +
                                                                                                                                                                                                                                                              shortest side of ABC, which is AB.
                   25. The statement is false. A rectangle                                                                                                                                                                                                    Thus, X corresponds to A.
                                                                                                                                                                               possible to find the indicated length.
                       measuring 5 units by 2 units is not similar
                       to a rectangle measuring 4 units by                                                                                                                  9. The triangles are similar by AA Similarity.
                       3 units.                                                                                                                                                QR 0.96
                   27. The statement is false.
                                                                                                                                                                        11. The ratios are not equal, so the two
                                                                                                                                                                            triangles are not similar.
                                                                                                                                                                        13.      +ABC a +BDC by SSS Similarity.
Selected Answers
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                                                                                              57                                                                                                                                                   58
                                                                                                                                                                                               Selected Answers
                                                                                                                                                                                               Selected Answers
Selected Answers
                       5. 20
                                                                                                                                                                                                                                                            §      1·     §     1·
                       7. MN & QR                                                                                                                                                                                                                       19. ¨ 1,  ¸ and ¨ 1, 1 ¸
                                                                                                                                                                                                                                                            ©      3¹     ©     3¹
                       9. LN & AB                                                                                                                                                                                                                       21. B
                   11. 0.24 kilometer                                                                                                                                                                                                                         E
                   13. Determine a line                                                                                                                                                                                                                 23. Point P must be closer to point B than to
                                                                                                                                                                        Evaluate                                                                            point A, so the coordinate of point P
                            Triangle Proportionality Theorem
                                                                                                                                                                            1. 20                                                                           should be positive.
                            Triangle Proportionality Theorem
                                                                                                                                                                            3. 17                                                                             Sample answer: The student found the
                            Transitive                                                                                                                                                                                                                                                    2
                                                                                                                                                                            5. (6, 1)                                                                                                       of the
                                                                                                                                                                                                                                                              coordinate of the point that is
                   15. C and E                                                                                                                                                                                                                                                            3
                                                                                                                                                                            7. (3, 3)
                   17. a. midsegment                                                                                                                                                                                                                          distance from B to A.
                                                                                                                                                                            9.
                               median                                                                                                                                                                                                                                            §8   1·
                                                                                                                                                                                                                                                        25. If point P is on RS, ¨ , 2 ¸ . There is
                               substitution                                                                                                                                                                                                                                      © 9 9¹
                               Triangle Proportionality                                                                                                                                                                                                       also a point P, not on RS, that lies
                            b. Can repeat the same process twice to                                                                                                                                                                                           beyond point S (32, 11).
                                                           2
                               show that Z is also located of the
                                                           3
                               distance from vertices A and B of
                               +  ABC to the midpoints of their
                               opposite sides.
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                                                                                              59                                                                                                                                                   60
                         1                                                                                                                                                  7.       70
                   11. 10 feet, or 10 feet 4 inches
                         3                                                                                                                                                     3 5
                                                                                                                                                                            9.
                   13. 304 inches or 25 feet 4 inches                                                                                                                           10
                   15. 69 inches or 5 feet 9 inches                                                                                                                     11. x         20 3
                   17.    +XYZ a +VUZ by the SAS Similarity
 SA31
                                              XY        XZ                                                                                                                       y    10 21
                         Criterion, so                     . Then
                                              VU        VZ                                                                                                                       z    20 7
                          XY        800                                                                                                                                 13. e
                                        , so XY            1,000 ft.
                          500       400
                                                                                                                                                                        15. d
                   19. A                                                                                                                                                17. a
                         B                                                                                                                                              19. 2.4
                         E
                                                                                                                                                                        21. | 4.62
                   21. AB is the shortest side of right ABE, so             +                                                                                           23. 4 inches and 16 inches
                       corresponding side DC of DCE must            +
                       be shorter than DE, that is, DE  200.
                       The triangles are similar, but Andy must
                       have used the wrong proportion. The
                                               d     200
                       correct proportion is              , so
                                              147    300
                                § 200 ·
                       d 147 ¨             98. The distance across
                                © 300 ¹¸
                       the river is 98 ft.
Selected Answers
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                                                                                                                                                                                               Selected Answers
                                                                                                                                                                                               Selected Answers
Selected Answers
                            tanP        6.33                                                                                                                                    7
                                                                                                                                                                            7.      | 0.28
                       7. tanA          2.0                                                                                                                                     25
                       9. QR       4.0                                                                                                                                      9. 9.0 | x
                   11. PQ          0.79                                                                                                                                 11. | 54.1
                   13. AB          8.4                                                                                                                                  13. | 64q
                   15. mA           66q                                                                                                                                15. | 47q
                   17. mB           43q                                                                                                                                17. A # A and ABC # ADE, since both
                                     38                                                                                                                                     are right angles.
                   19. PQ 
                                   tan75q
                                                 10.2
                                                                                                                                                                                            +
                                                                                                                                                                                 By AA~, ABC~ ADE, so     +
                                                                                                                                                                                 corresponding sides are proportional
                   21. 60q
                                                                                                                                                                                 AC     BC                  (BC )( AE )   AC                AE
                   23. The student’s calculations are correct only                                                                                                                          AC                         
                       if the triangle is a right triangle.                                                                                                                      AE     DE                     DE         BC                DE
                   25. 10.2q with the first road and 79.8q with the                                                                                                              These ratios determine sin A, and since
                       second road.                                                                                                                                              they are equal, sin A is the same when
                                                                                                                                                                                 calculated in either right triangle.
                                                                                                                                                                        19. 9.5 ft
                                                                                                                                                                        21. 66q and 24q
                                                                                                                                                                                 Check 66q  24q            90q
                                                                                                                                                                        23. So mBAC 2mBAD
                                                                                                                                                                                    § 100 ·
                                                                                                                                                                             2sin1 ¨      ¸ | 9.7q 
                                                                                                                                                                                    © 1185 ¹
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                                                                                              65                                                                                                                                                    66
                                                                                                                                                                                               Selected Answers
                                                                                                                                                                                               Selected Answers
Selected Answers
                   13. mC           10qa | 51.8; b | 35.5                                                                                                                5. p | 25.0; mR | 42.1q; mQ | 14.9q
                   15. No triangles are possible.                                                                                                                           7. mP | 25.2q; mR | 58.4q; mQ | 96.4q
                   17. There are two triangles.                                                                                                                             9. mR | 93.8q; mQ | 29.9q; mP                            56.3q
                            mB | 39.6qmC                105.4qc | 15.1 m                                                                                          11. b | 6.5; mA | 64.9q; mC                         37.1q
                            Second triangle                                                                                                                             13. mA |94.8q; mB | 39.8q;
                            mB |140.4qmC                 4.6qc | 1.3 m                                                                                                     mC      45.4q
                   19. a. | 123.7 mi                                                                                                                                    15. mA | 56.6q; mB | 46.4q; mC                               77.0q
                            b. Possible answer Calculate the area                                                                                                      17. 3.8 miles
                               using the sine formula. Use the value of
                               the area to solve for h using the other                                                                                                  19. D. 45q
                               form of the area formula.                                                                                                                21. mA | 45q; mB | 60q; mC | 74q
                               | 120 mi                                                                                                                                 23. 1.2 km
                   21. | 5.2 mi                                                                                                                                         25. Abby did not make an error. The three
                   23. Transfer corresponding angle measures                                                                                                                lengths cannot form a triangle because
                       from each triangle to the other.                                                                                                                     a  b c.
                   25. f | 2.1; e | 3.7
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                                                                                              67                                                                                                                                                   68
mW 94q
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                                                                                                                                                                                                                                                                      1                  1 2
                                                                                                                                                                                                                                                              3.          x2              x
                                                                                                                                                                                                                                                                   4( 5)               20
                                                                                                   13. The graph of the circle intersects the                                                                                                                 5. Focus (0, 6); directrix is y                   6.
                                                                                                       x-axis at both (3, 0) and (3, 0).
                                                                                                                                                                                                                                                                        §     1·                                       1
                   12. The point                     
                                             18, 4 does not lie on the                            15. (x  1)2  (y  2)2              4                                                                                                                     7. Focus ¨ 0,  ¸ ; directrix is y
                                                                                                                                                                                                                                                                        ©     2¹                                       2
                                                                                                                                                                                                                                                                                                                         .
                         circle because the point’s x- and                                         17. The point does lie on the equation
                                                                                                       because its x- and y coordinates satisfy                                 9. (x  2)2      16(y  5)                                                   9. (x  2)2         8 (y  5)
                         y-coordinates do not satisfy the equation
                         of the circle.                                                                the equation 02  4(0)  42  4(4) 0
                   13. The point (4, 4) lies on the circle                                        19. False; r                 7
                       because the point’s x- and y-coordinates                                    21. False; the center is (6, 4), which is in the
                       satisfy the equation of the circle.                                             fourth quadrant.
                   Evaluate                                                                        23. False; the equation is x2  y2                      32     9
                       1. (h, k)                                                                   25. a. (x  3)2  (y  3)2               10
                       3. (x  1)2  (y  3)2             64                                             b. It does lie on the circle because x                         0
                       5. (x  9)2  y2        3                                                            and y 4 satisfies the equation
                                                                                                            (x  3)2  (y  3)2 10
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a sphere
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                       3. 1764S in2
                                                                                                                                                                            9. For the model, the volume is 64S cu. in.,
                       5. 196S cm2                                                                                                                                             and the surface area is 60Ssq. in. For the
                       7. 180S in2                                                                                                                                             silo, the volume is 2985984S cu. in. and
                                                                                                                                                                               the surface area is 77760S sq. in. The
                       9. | 1332.0 mm 2
                                                                                                                                                                               volume changes by a factor of 363 , and
                   11. 2S          15 in.                                                                                                                                      the surface area changes by a factor
                   13. 9S in2                                                                                                                                                  of 362.
                                        4                                                                                                                               Evaluate
                   15. Susana used        , which is part of the
                                        3                                                                                                                                                                              1
                          volume formula, not the surface area                                                                                                              1. The area is multiplied by                 .
                                                                                                                                                                                                                       2
                          formula. The surface area formula is
                          4S r 2 .                                                                                                                                          3. The area is multiplied by
                                                                                                                                                                                                                       1
                                                                                                                                                                                                                         .
                                                                                                                                                                                                                       4
                   17. 144S in2
                                                                                                                                                                            5. The area is doubled.
                                                                                                                                                                                                                       2
                                                                                                                                                                            7. The area is multiplied by                 .
                                                                                                                                                                                                                       3
                                                                                                                                                                            9. The perimeter is tripled. The area is
                                                                                                                                                                               multiplied by 9.
                                                                                                                                                                        11. Volume is multiplied by 125.
                                                                                                                                                                        13. A. non-proportional; B. proportional;
                                                                                                                                                                            C. non-proportional; D. non-proportional;
                                                                                                                                                                            E. proportional
                                                                                                                                                                        15. | 800,000 acres
                                                                                                                                                                        17. 36 in.
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                       7. | 11.8%                                                                                                                                       11.
                                                                                                                                                                                  1
                          193                                                                                                                                                    15
                       9.
                          512                                                                                                                                                    58
                                                                                                                                                                        13.
                       93                                                                                                                                                        75
                   11.                                                                                                                                                           61
                       256                                                                                                                                              15.
                                                                                                                                                                                 75
                        1
                   13.                                                                                                                                                            5
                       220                                                                                                                                              17.
                                                                                                                                                                                 18
                       4
                   15.                                                                                                                                                            7
                       21                                                                                                                                               19.
                                                                                                                                                                                 18
                        1
                   17.                                                                                                                                                            7
                       435                                                                                                                                              21.
                                                                                                                                                                                 12
                        14
                   19.                                                                                                                                                  23. 85%
                       969
                                                                                                                                                                        25. When finding n( A  B ), n( A) should be
                   21. a. 84
                                                                                                                                                                            added to n(B), not multiplied.
                               5
                            b.                                                                                                                                               4
                               21
                                                                                                                                                                            13
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                                                                                                                                                                                   19                                                                                             5 3 15
                            1                                                                                                                                                                                                                                                   40     4
                       9.                                                                                                                                                     d. Events R and B are independent when                                           P (W  Pe )                 and
                            2                                                                                                                                                    the first chip is returned to the bag                                                        150 15
                                                                                                                                                                                 because P (B~R ) P (B ) in that case                                          P (W  Pe ) P (W ) < P (Pe ), the events
                            1
                   11.                                                                                                                                                                                                                                         are independent.
                            4
                            1                                                                                                                                           21. P ( A ~B ) 1  P ( A~B )
                                                                                                                                                                                 c
                                                                                                                                                                                                                   Definition of complementary events
                   13.
                            2                                                                                                                                                          1  P ( A)                  Definition of independent events
                   15. A. B                                                                                                                                                                   P ( Ac )             Definition of complementary events
                            B. D                                                                                                                                               So, events Ac and B are also independent.
                            C. A
                            D. C
                   17. 45%
                             5
                   19.
                             6
                            Given that not rolling a 1 on the red
                            number cube has occurred, there are 30
                            possible outcomes:
                            (2, 1), (2, 2), (2, 3), (2, 4), (2, 5), (2, 6),
                            (3, 1), (3, 2), (3, 4), (3, 5), (3, 6), (4, 1),
                            (4, 2), (4, 3), (4, 4), (4, 5), (4, 6), (5, 1),
                            (5, 2), (5, 3), (5, 4), (5, 5), (5, 6), (6, 1),
                            (6, 2), (6, 3), (6, 4), (6, 5), and (6, 6).
                            all but 5 outcomes—(2, 1), (3, 1), (4, 1),
                            (5, 1), and (6, 1)—are successful
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                       8. 69%
                         The probability of the test being correct in
                         this case increases about 2%.
                       9. 31%
                         The probability of the test being correct in
 SA50
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