Question

Construct the following angle using ruler and compass only

120°

Answer 1

Construction:

We know that there are two 60° angles in 120°.

∴ We can construct two 60° angles consecutively construct 120°

Step 1: Drawn a line and marked a point ‘A’ on it.

Step 2: With ‘A’ as center, drawn an arc of convenient radius to the line at a point B.

Step 3: With the same radius and B as center, drawn an arc to cut the previous arc at C.

Step 4: With the same radius and C as center, drawn an arc to cut the arc drawn in step 2 at D.

Step 5: Joined AD. Then ∠BAD is the required angle with measure of 120°.