# How do you write an equation for a circle with center (5,5) with a radius of 7?

Jul 24, 2016

${\left(x - 5\right)}^{2} + {\left(y - 5\right)}^{2} = {7}^{2}$

#### Explanation:

The equation of a circle with centre $\left(h , k\right)$ and radius $r$ can be written:

${\left(x - h\right)}^{2} + {\left(y - k\right)}^{2} = {r}^{2}$

So in our example, the equation of the circle can be written:

${\left(x - 5\right)}^{2} + {\left(y - 5\right)}^{2} = {7}^{2}$

graph{((x-5)^2+(y-5)^2-7^2)((x-5)^2+(y-5)^2-0.04)=0 [-18.09, 21.91, -5.76, 14.24]}