The point (7,-9) lies on a circle. What is the length of the radius of this circle if the center is located at (5,-7)?

Answer 1

(x-5)^2 + (y+7)^2 = r^2

(7-5)^2+(-9+7)^2 = 8= t^2

r= sqr8= 2sqr2 = about 2.828 = radius