SOLUTION: find the center (h,k) and radius r of the circle x^2+y^-4x+2y=20 by completing the circle

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Question 358660: find the center (h,k) and radius r of the circle x^2+y^-4x+2y=20 by completing the circle
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
+x%5E2%2By%5E2-4x%2B2y=20+
%28x%5E2-4x%29%2B%28y%5E2%2B2y%29=20
+%28x%5E2-4x%2B4%29%2B%28y%5E2%2B2y%2B1%29=20%2B4%2B1
%28x-2%29%5E2%2B%28y%2B1%29%5E2=25
%28x-2%29%5E2%2B%28y%2B1%29%5E2=5%5E2
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Compare to %28x-h%29%5E2%2B%28y-k%29%5E2=r%5E2
.
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(h,k)=(2,-1)
r=5