Find the equation of the circle that passes through the point P(1, 7) and whose center is the point C(4, 3). Then sketch its graph.

Answer 1

you have the center at (4,3), so the equation is

(x-4)^2 + (y-3)^2 = r^2

Now you just need r. Since the point (1,7) is on the circle, plug it in:

(1-4)^2 + (7-3)^2 = 9+16 = 25

So,

(x-4)^2 + (y-3)^2 = 25