Question

A _______ is the angle that forms when two radii meet at the center of a circle.

• A. middle angle
• B. central angle
• C. side angle
• D. second angle

Answer 1

The correct option is B central angle

Two radii of a circle form the two equal sides of an isosceles triangle.

here AB=AC

and $\angle ABC=\angle ACB$

so ,$\angle ABC+\angle ACB+\angle BAC={180}^{\circ }$

therfore $\angle A={180}^{\circ }-2\angle B$ [because $\angle B=\angle C$]