# How do you write an equation for a circle with center (3,0) and the radius is 1?

Aug 20, 2016

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

#### Explanation:

The standard form of the equation of a circle is.

$\textcolor{red}{| \overline{\underline{\textcolor{w h i t e}{\frac{a}{a}} \textcolor{b l a c k}{{\left(x - a\right)}^{2} + {\left(y - b\right)}^{2} = {r}^{2}} \textcolor{w h i t e}{\frac{a}{a}} |}}}$
where (a ,b) are the coordinates of the centre and r, the radius.

here a = 3, b= 0 and r = 1

substitute these values into the equation.

${\left(x - 3\right)}^{2} + {\left(y - 0\right)}^{2} = {1}^{2}$

$\Rightarrow {\left(x - 3\right)}^{2} + {y}^{2} = 1 \text{ is the equation of the circle}$