SOLUTION: Find the CENTER and the LENGTH of a radius of the circle. x2 + y2 + 16x + 4y + 59 = 0

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Question 457912: Find the CENTER and the LENGTH of a radius of the circle.
x2 + y2 + 16x + 4y + 59 = 0
Found 2 solutions by robertb, stanbon:
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
The expression x%5E2+%2B+y%5E2+%2B+16x+%2B+4y+%2B+59+=+0 is equivalent to
%28x%2B8%29%5E2+%2B+%28y%2B2%29%5E2+=+9
The center of the circle is then (-8, -2) and the radius is sqrt%289%29+=+3.

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Find the CENTER and the LENGTH of a radius of the circle.
x^2 + y^2 + 16x + 4y + 59 = 0
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Complete the square on the x-terms and on the y-terms.
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x^2+16x+64 + y^2+4y+4 = -59+64+4
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(x+8)^2 + (y+2)^2 = 9
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center at (-8,-2)
radius = sqrt(9) = 3
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Cheers,
Stan H.