# The center of a circle is at (7, -3) and it has a radius of 9. What is the equation of the circle?

##### 1 Answer

Apr 9, 2018

#### Explanation:

#"the equation of a circle in standard form is"#

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

#"where "(a,b)" are the coordinates of the centre and r is"#

#"the radius"#

#"here "(a,b)=(7,-3)" and "r=9#

#(x-7)^2+(y-(-3))^2=9^2#

#rArr(x-7)^2+(y+3)^2=81larrcolor(red)"equation of circle"#