factor it as perfect squares
x^2-6x + 9 + y^2+2y + 1= 15+9+1
(x-3)^2 + (y+1)^2=25
so center is 3,1 and radius is 5
The equation of a circle is x^2-6x+y^2+2y=15
what is the center and the radius?
2 answers
oops, center 3,-1