Question

Construct an angle of ${90}^{\circ }$ at the initial point of the given ray. Write down the steps of construction.

Answer 1

Step 1: Draw a ray OA
Step 2: With O as centre and any convenient radius, draw an arc, cutting OA at P.
Step 3: With P as centre and same radius, draw an arc cutting the arc drawn in step 2 at Q
Step 4: With Q as centre and the same radius as in steps 2 and 3, draw an arc, cutting the arc drawn in step 2 at R.
Step 5: With Q and R as centres and same radius, draw two arcs, cutting each other at S.
Step 6: Join OS and produce to B. Thus, $\angle$AOB is the required angle of ${90}^{\circ }$.