# How do you write an equation for a circle with center (-11, 3) and radius r = 9?

${\left(x + 11\right)}^{2} + {\left(y - 3\right)}^{2} = 81$
To do this, we'll us the standard equation of a circle: ${\left(x - h\right)}^{2} + {\left(y - k\right)}^{2} = {r}^{2}$, where $h , k$ are the coordinates of the centre, and $r$ is the radius of the circle. Applying this, we get:
${\left(x + 11\right)}^{2} + {\left(y - 3\right)}^{2} = 81$