Question

In the given figure, $O$ is the centre of the circle and $\angle AOB={70}^o$. Calculate the value of $\angle OAC$.

Answer 1

From the figure we know that the radius is

$OA=OC$

We know that the base angles of an isosceles triangle are equal

$\angle OAC=\angle OCA$

It is given that $\angle OCA={35}^o$

So we get

$\angle OAC={35}^o$

Therefore, $\angle OAC={35}^o$