Point O is the center of the circle on which points A, B and C lie. It is known that ∠ABC = 15 °

Point O is the center of the circle on which points A, B and C lie. It is known that ∠ABC = 15 ° and ∠OAB = 8 °. Find the BCO angle.

Solution to the above problem:
First, draw the radius OB and consider the triangle AOB:
AO = OB (since these are the radii of the circle), which means the angle OAB = angle ABO = 8 degrees.
Consider a triangle BOC:
BO = OC (since these are the radii of the circle), therefore angle BCO = angle OBC = angle ABC – angle ABO.
Let’s substitute the values we know. The following expression will turn out:
15 degrees – 8 degrees = 7 degrees.
The correct answer to the problem: the BCO angle is seven degrees.