
William W. answered 02/07/23
Top ACT Math Prep Tutor
The general form of a circle is (x - h)2 + (y - k)2 = r2 where (h, k) is the center of the circle and "r" is the radius of that circle. We have the center, so we can plug in h = -6 and k = 5:
(x + 6)2 + (y - 5)2 = r2
We have a point on the circle (3. 5) which is x = 3 and y = 5 so we can plug that into our equation and solve for "r":
(3 + 6)2 + (5 - 5)2 = r2
92 + 02 = r2
r = 9
So, plugging that into our equation, we get: (x + 6)2 + (y - 5)2 = 81