SOLUTION: Find the center and radius of the circle (x-5)2 + y2 + 2y=7

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Question 148286: Find the center and radius of the circle (x-5)2 + y2 + 2y=7
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Find the center and radius of the circle (x-5)2 + y2 + 2y=7
Put in the form %28x-a%29%5E2%2B%28y-b%29%5E2+=+r%5E2
x is ok as it is.
Complete the square for y
y%5E2%2B2y%2B1+=+%28y%2B1%29%5E2, so add 1 to both sides:
%28x-5%29%5E2%2B%28y-%28-1%29%29%5E2+=+8
The center is at (a,b), or (5,-1) and the radius is sqrt%288%29.
sqrt%288%29+=+2sqrt%282%29