Question

What is the equation of a circle with center (−3, 0) and radius 20?

Answer 1

(x + 3)^2 + y^2 = 20^2

Explanation:

If the center is (-3, 0), then the standard equation of a circle, (x - h)^2 + (y - k)^2 = r^2 becomes (x + 3)^2 + (y - 0)^2 = 20^2, or

(x + 3)^2 + y^2 = 20^2