Question

A circle has a center at 4 – 5i and a point on the circle at 19 – 13i. Which of the following points is also on the circle

Answer 1

Distance^2 between points(=radius^2)
= (19-4)^2 + (-13-(-5))^2 = 15^2 + 8^2
= 289
compare with distance^2 in each choice to center
12 + 10i is correct (equal distance)