# How do you write an equation for a circle with center at (3, -6); radius = 5?

Aug 8, 2018

${\left(x - 3\right)}^{2} + {\left(y + 6\right)}^{2} = 25$

#### Explanation:

$\text{the equation of a circle in standard form is}$

$\textcolor{red}{\overline{\underline{| \textcolor{w h i t e}{\frac{2}{2}} \textcolor{b l a c k}{{\left(x - a\right)}^{2} + {\left(y - b\right)}^{2} = {r}^{2}} \textcolor{w h i t e}{\frac{2}{2}} |}}}$

$\text{where "(a,b)" are the coordinates of the centre and r}$
$\text{is the radius}$

$\text{here "(a,b)=(3,-6)" and } r = 5$

${\left(x - 3\right)}^{2} + {\left(y + 6\right)}^{2} = 25 \leftarrow \textcolor{red}{\text{ is equation of circle}}$