# How do you find the center and radius of ( x - 3 )^ 2 + y ^2 = 4?

Dec 2, 2016

The center is $\left(3 , 0\right)$ and the radius $= 2$

#### Explanation:

The equation of a circle is

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

The center is $\left(a , b\right)$ and the radius $r$

We compare this to your equation

${\left(x - 3\right)}^{2} + {\left(y - 0\right)}^{2} = {2}^{2}$

So,

The center is $\left(3 , 0\right)$ and the radius $= 2$

graph{(x-3)^2+(y)^2=4 [-6.24, 6.244, -3.12, 3.12]}