Question

1 point
. In the figure, if O is the
centre of the circle, then the
measure of x is:
​

Answer 1

Angle AOB = 2× Angle ACB ( inscribed angle theorem )

Angle AOB = 2 × 40° = 80°

OA = OB ( radius )

As OA = OB, we can say that ∆AOB is isosceles.

so, angle A = angle B taking them as base angles.

so, let angle A and B be x° respectively.

Angle A + Angle B + Angle O = 180° ( angle sum property )

x° + x° + 80° = 180°

2x° + 80° = 180°

2x° = 180° - 80°

x° = 100/2 = 50°

therefore, the measure of x is 50°