Question

In the given figure, if ∠ABC = 20∘ , then ∠AOC is equal to ____________.

Answer 1

Given:
∠ABC = 20° ...(1)


We know, the angle subtended by an arc at the centre is twice the angle subtended by it at the remaining part of the circle.
Thus, ∠AOC = 2∠ABC
⇒ ∠AOC = 2(20°) (From (1))
⇒ ∠AOC = 40°

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Hence, ∠AOC is equal to 40°.