# How do you write the equation of the circle with center (-1,3) and radius 3?

##### 1 Answer

Oct 8, 2016

#### Explanation:

The standard form of the equation of a circle is.

#color(red)(bar(ul(|color(white)(a/a)color(black)((x-a)^2+(y-b)^2=r^2)color(white)(a/a)|)))#

where (a ,b) are the coordinates of the centre and r, the radius.here a = -1 , b = 3 and r = 3

substitute values into the standard equation.

#(x-(-1))^2+(y-3)^2=3^2#

#rArr(x+1)^2+(y-3)^2=9" is the equation of the circle"#