Question

In Fig. 5, 'O' is the centre of a circle and
angle OBA = 60°. Then angle ACB equals​

Answer 1

Step-by-step explanation:

Consider △AOB.

OA=OB⇒∠OAB=∠OBA=60

o

By angle sum property, we get, ∠AOB=60

o

Angle in subtended at the center is twice the angle subtended anywhere on the arc, so

∠ACB=

2

1

∠AOB=30

o

Answer 2

Answer:

Consider △AOB.

OA=OB⇒∠OAB=∠OBA=60

By angle sum property, we get, ∠AOB=60

Angle in subtended at the center is twice the angle subtended anywhere on the arc, so

∠ACB=2 +1

∠AOB=30