Question

In the given figure, AB is a chord of a circle with centre O. If angle OAB = 50°, then angle ACB is :
(A) 40°
(C) 100
(B) 50°
(D) 25°​

Answer 1

Answer:

A 40°

Step-by-step explanation:

OA=OB (radii of same circle)

Angle OAB=ANGLE OBA (angle opposite to congruent side)

Angle OAB=AngleOBA=50°

IN triangle OAB

ANGLE AOB=80°(remaining angle of a triangle)

Measure arc AB=Measure angle AOB (defination of minor arc)

Measure of arc AB =80°

Angle ACB=1/2*Measure arc AB(Inscribed angle theorem)

=1/2*80°

=40°