Question

AB is a diameter of the

circle. Find the angle
BCO.

A 70°
B 20°
C 60°
D50°

Answer 1

70°, ,have a nice day

Answer 2

∠BCO = 70°

Explanation:

AO = CO = BO because all radii of the same circle are equal.

∠ACO = 20° because it is an isosceles triangle.

∠BCA = 90° because a triangle with it's hypotenuse being the diameter of a circle is a right triangle.

∠BCA - ∠ACO = ∠BCO

90° - 20° = 70°

∠BCO = 70°