Question

In the given figure, O is the centre of a circle and $\angle OAB={50}^{\circ }.\text{Then,}\angle CDA=?$

(a) ${40}^{\circ }$

(b) ${50}^{\circ }$

(c) ${75}^{\circ }$

(d) ${25}^{\circ }$

Answer 1

(b) 50°
We have:
OA = OB (Radii of a circle)
⇒ ∠OBA = ∠OAB = 50°
∴ ∠CDA = ∠OBA = 50° (Angles in thesame segment of a circle)