Algebra
posted by Britney on .
State the center and the radius of the circle represented by the equation
(x + 1)^2 + (y – 5)^2 = 64

If you tried to copy and paste, that does not work here.

State the center and the radius of the circle represented by the equation
(x + 1^2 + (y – 5)^2 = 64 
I think the radius is 8 but am stuck on what the center represents here.

You mean (x+1)^2
Now this is the same both sides of x = 1
Like for x = 2 and for x = 0
in both cases (x+1)^2 = +1
In other words, x = 1 is an axis of symmetry and the circle center must lie on x = 1
Same thing for y = 5
so the center is at (1,+5)
NOW
in general:
(xh)^2 + (yk)^2 = r^2
is circle with radius r
and center at (h,k) 
I did get (1,5) as well, but why is it 1 rather than 1? I was just wondering.

(xh) = (x+1)
so
h = +1
h = 1