Question

A circle has a center at A (4,5), Determine the radius of the circle given two end points of the circle are B (9,5) and C (-1,5)

Answer 1

The center-radius form of the circle equation is in the format (x – h)2 + (y – k)2 = r2, with the center being at the point (h, k) and the radius being "r". This form of the equation is helpful, since you can easily find the center and the radius.