Question

In Fig. 6.2, POQ is a line. The value of x is

Let OA, OB, OC and OD are rays in the anticlockwise direction such that ∠AOB = ∠COD = 100°, ∠BOC = 82° and ∠AOD = 78°. Is it true to say that AOC and BOD are lines?

For what value of x + y in Fig. 6.4 will ABC be a line? Justify your answer.

In Fig. 6.9, OD is the bisector of ∠AOC, OE is the bisector of ∠BOC and OD ⊥ OE. Show that the points A, O and B are collinear.