Question

What's the equation for a circle with a center of (-2, 1) and a radius of 3.​

Answer 1

`(x+2)^2 + (y-1)^2 = 9`

Explanation:

The equation of a circle is written with the center and radius into the vertex form
`(x-h)^2 + (y-k)^2 = r^2`.

Here h = -2 and k = 1. Substitute these values with r = 3.

`(x--2)^2 + (y-1)^2 = 3^2\\(x+2)^2 + (y-1)^2 = 9`