Step 2 :
(i) With ‘O’ as center draw an arc of any radius to cut the line
at A.
(ii) With the same radius and A as center draw an arc to cut
the
previous arc at B.
Step 3
Example 2 :
Construct an acute angle of 30°.
Step 1 :
(i) First let us construct 60° angle and then bisect it to get
30° angle.
(ii) Construct 60° (as shown in the above example).
Step 2 :
AB in the interior of ∠AOB.
(i) With ‘A’ as center, draw an arc of radius more than half of
(ii) With the same radius and with B as center draw an arc to
cut the previous one at C.
(iii) Join OC.
(iv) We get the required angle ∠AOC = 30°.
Example 3 :
Construct an obtuse angle of 120°.
Step 1 :
Draw a line ‘l’ and mark a point ‘O’ on it.
Step 2 :
With ‘O’ as center draw an arc of any radius to cut the line l
at A.
Step 3 :
(i) With same radius and with ‘A’ as center draw another arc
to cut the previous arc at ‘B’.
(ii) With ‘B’ as center draw another arc of same radius to cut
the first arc at ‘C’.
Step 4 :
(i) Join OC.
(ii) We get the required angle ∠AOC = 120°.
Example 4 :
Construct a right angle 90°.
Step 1 :
(i) To construct 90° angle, we are going to bisect the straight
angle 180°.
(ii) Mark a point ‘O’ on a straight line ‘l’.
Step 2 :
(i) With ‘O’ as center draw arcs of any radius to cut the line l
at A and B.
(ii) Now ∠AOB = 180°.
Step 3 :
With A and B as centers and with the radius more than half of
AB draw arcs above AB to intersect each other at ‘C’.
Step 4 :
(i) Join OC.
(ii) We get the required angle ∠AOC = 90°.
