# How do you find the center and radius of the circle (x+4)^2+y^2=49?

Oct 11, 2016

Center of the circle is $\left(- 4 , 0\right)$ and radius is $7$

#### Explanation:

Equation of a circle with center at $\left(h , k\right)$ and radius $r$ is given by

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

Hence ${\left(x + 4\right)}^{2} + {y}^{2} = 49$

$\Leftrightarrow {\left(x - \left(- 4\right)\right)}^{2} + {\left(y - 0\right)}^{2} = {7}^{2}$

Hence center of this circle is $\left(- 4 , 0\right)$ and radius is $7$
graph{(x+4)^2+y^2=49 [-24.58, 15.42, -9.92, 10.08]}