Draw an angle of 80° with the help of a protractor. Then construct angles of

(i) 40° (ii)160° and (iii) 120°.

(i)

Step 1:

Draw ∠AOB = 80° and with any radius and A as center draw an arc.

Step 2:

With X as center and radius more than half of XY draw an arc and with Y as center and equal radius draw an arc and let the arcs intersect at C.

Step 3:

Join OC.

∠COB is equal to 40°.

Step 4:

With Y as center and radius more than half of PY draw an arc and with P as center and equal radius draw an arc and let the arcs intersect at D.

Step 5:

Join OD.

∠DOB is 60°.

Step 6:

With O as center and OX as radius extend the Arc XY to Arc XY’.

Step 7:

With Q as center and XQ as radius, draw an arc which cuts the Arc XY’ at R.

Step 8:

Join RO.

∠ROB is 120°.