Question

In given figure, $\angle ABC={45}^{\circ },$ find $\angle AOC$.

Answer 1

We know that, in a circle, the angle subtended by an arc at the center is twice the angle subtended by it at the remaining part of the circle.

Since, $\angle ABC=\frac{1}{2}\angle AOC$
$⟹\angle AOC=2\angle ABC=2\times {45}^{\circ }={90}^{\circ }$