SOLUTION: What point is the center of the circle with equation x^2+y^2-6x+2y-6=0? A.(3,1) B.(9,1) C.(-3,-1) D.(3,-1) E.(-3,1) THANKS

Algebra ->  Quadratic-relations-and-conic-sections -> SOLUTION: What point is the center of the circle with equation x^2+y^2-6x+2y-6=0? A.(3,1) B.(9,1) C.(-3,-1) D.(3,-1) E.(-3,1) THANKS      Log On


   

Question 181823: What point is the center of the circle with equation
x^2+y^2-6x+2y-6=0?
A.(3,1) B.(9,1) C.(-3,-1) D.(3,-1) E.(-3,1)
THANKS
Answer by Mathtut(3670) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2By%5E2-6x%2B2y-6=0
:
%28x%5E2-6x%2B9%29%2B%28y%5E2%2B2y%2B1%29-6-9-1=0setting up to complete squares on x an y terms
:
%28x-3%29%5E2%2B%28y%2B1%29%5E2=16
:
so the center is at (3,-1)
:
D is the answer