Question

The circle below is centered at (10,4) and has a radius of 4. What it’s equation?

Answer 1

`(x-10)^2 + (y-4)^2 = 16`

Explanation:

To write the equation using a center and a radius, use the vertex form of the equation.

`(x-h)^2+(y-k)^2 = r^2`

Substitute the values h=10 and k=4 into the equation along with r = 4.

`(x-10)^2 + (y-4)^2 + 4^2\\(x-10)^2 + (y-4)^2 = 16`