The center of a circle is at (-2, 3) and it has a radius of 3. What is the equation of the circle?

2 Answers
Feb 14, 2016

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

Explanation:

Standard Equation of a Circle:
#(x - h)^2 + (y - k)^2 = r^2#

where
#C: (h, k)#
#r# = radius

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

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

Feb 14, 2016

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

Explanation:

the standard form of the equation of a circle is

# (x-a)^2 + (y-b)^2 = r^2#
where (a , b) are the coords of the centre and r , the radius.

here (a , b ) = ( -2 , 3 ) and r = 3
substitute these values into the equation to obtain

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