<PRE><B>Question 972349</B>
Find the center and radius of the circle whose equation is 
x2 + 2x + y2 – 4y + 1 = 0.
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Complete the square on the x and on the y terms::
x^2 + 2x + 1 + y^2 - 4y + 4 = -1 + 1 + 4
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Factor::
(x+1)^2 + (y-2)^2 = 4
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Center = (-1,2)
Radius = sqrt(4) = 2
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Cheers,
Stan H.
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