Question

Find the equation of the circle with a center at (-1,3) and a radius of 4.

Answer 1

(x + 1)^2 + (y - 3)^2 = 16.

Explanation:

The standard form is

(x - h)^2 + (y - k)^2 = r^2 - (h, k) = center and r = radius

So we see with the given values our equation is:

(x - (-1))^2 + (y - 3)^2 = 4^2

(x + 1)^2 + (y - 3)^2 = 16.