The radius of a circle given C (4,-1) and (8,2). What is the equation that defines the circle if its center is at the fourth quadrant?

Answer 1

if you mean that the center is (4,-1) and (8,2) lies on the circle, then

r^2 = (8-4)^2+(2+1)^2 = 25

so the circle is

(x-4)^2 + (y+1)^2 = 25

Answer 2

Math