Question

In the given figure, O is the centre of a circle. If ∠OAB = 40° and C is a point on the circle, then ∠ACB =​

Answer 1

Answer:

∠ACB = 50°

Step-by-step explanation:

∠OAB = ∠OBC = 40° ( Reason : OA = OB )

∠OAB + ∠OBC + ∠AOB = 180° ( Angle sum property of triangle )

40° + 40° + ∠AOB = 180°

80° + ∠AOB = 180°

∠AOB = 180° - 80°

∠AOB = 100°

∠ACB = ∠AOB / 2

= 100° / 2

∠ACB = 50°