# How do you find the center and radius of the circle with this equation: (x+6)^2 + (y-4)^2 = 36?

Jan 6, 2016

centre = ( -6 , 4 ) and radius = 6

#### Explanation:

the standard form of the equation of a circle is :

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

where (a , b ) represents the centre and r the radius.

compare the standard form to ${\left(x + 6\right)}^{2} + {\left(y - 4\right)}^{2} = 36$

$\Rightarrow a = - 6 , b = 4 \mathmr{and} r = \sqrt{36} = 6$

$\Rightarrow c e n t r e = \left(- 6 , 4\right) \mathmr{and} r a \mathrm{di} u s = 6$