Question

Given O is the centre of the circle and ∠AOB = 70°. Calculate the value of:

1. ∠OCA,
2. ∠OAC.

Answer 1

Here, ∠AOB = 2∠OCA  ...(Angle at the center is double the angle at the circumference by the same chord)

`=>` ∠ACB =`70/2` = 35°

Now, OC = OA   ...(Radii of same circle)

`=>` ∠OCA = ∠OAC = 35°