Name ________________________________________ Date __________________ Class __________________
LESSON
Cross-Sections and Solids of Rotation
19-1
Reteach
A net is a diagram of the surfaces of a three-dimensional figure.
If the net is folded along the lines in the figure in the same direction, the
folded net would form a rectangular prism.
The figure… can fold to form:
Name the three-dimensional figures that the nets would form.
1. _______________ 2. ___________________
A cross-section is a region of a plane that intersects a solid figure.
A cross-section is often a two-dimensional figure such as
a circle, parallelogram, or triangle.
In the figure, a cross-section of a cylinder is shown.
The cross-section is parallel to the bases of the cylinder.
So, the cross-section is a circle.
Draw the figures described below. Name the cross-section
of the figure.
3. A cylinder with a cross- 4. A cone with a cross- 5. A cone with a cross-
section perpendicular to section perpendicular to section parallel to the
the bases. the bases. bases.
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Reteach 17-2 3. rectangle
1 2
1. x 2 = 16 y ; y = x
16
1 2
2. x 2 = −4 y ; y = − x
4
3. ( x − 3 ) = −4 ( y − 1)
2
Reteach 18-1
4. triangle
1. 240 in3
2. 288 ft3
3. 625 cm3
4. 2010.62 cm3
5. 27 ft3
Reteach 18-2
1. 80 in3
5. circle
2. 128 in3
3. 41.67 m3
4. two pyramids and a rectangular prism
5. Vprism = 8 m3; Vpyramids ≈ 26.67 m3
6. V = 61.34 m3
Reteach 18-3
1. 113.10 ft3
2. 10,857.34 cm3
Reteach 19-2
3. 5,428,672.11 mm3
1. 54 cm2
4. cylinder; cone
2 108 cm2
3
5. 804.25 cm
3. 240 in2
3
6. 1072.33 cm
4. 502.65 in2
3
7. 1876.58 cm
5. 942.48 cm2
Reteach 18-4 6. 150.80 ft2
1. 904.78 cm3
Reteach 19-3
2. 2144.66 ft3
1. 48 ft2
3
3. 523.60 in
2. 252 cm2
4. cone; sphere
3. 400 ft2
3
5. 33.51 in
4. 301.59 ft2
3
6. 16.76 in
5. 763.41 m2
3
7. 50.27 in
6. 703.72 in2
Reteach 19-1 Reteach 19-4
1. cylinder
1. 804.25 in2
2. pyramid
2. 1809.56 cm2
3. 1256.64 ft2
Original content Copyright © by Houghton Mifflin Harcourt. Additions and changes to the original content are the responsibility of the instructor.
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