# How do you write the standard form of the equation of the circle with the given the center (-3,1) and radius of 7?

Jan 5, 2016

${\left(x + 3\right)}^{2} + {\left(y - 1\right)}^{2} = 49$

#### Explanation:

The standard form of the equation for a circle is

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

Where the center is $\left(h , k\right)$ and the radius is $r$.

Thus,

$h = - 3$
$k = 1$
$r = 7$

Plug these in to the standard form:

${\left(x - \left(- 3\right)\right)}^{2} + {\left(y - 1\right)}^{2} = {7}^{2}$

When simplified:

${\left(x + 3\right)}^{2} + {\left(y - 1\right)}^{2} = 49$