<PRE><B>Question 319800</B>
Find the coordinates of the center of the circle and length of the radius given the equation of that circle which is 5x^2+15x+5y^2-10y-10=0
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Divide thru by 5 to get:
x^2 + 3x + y^2 - 2y - 2 = 0
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Complete the square on the x-terms and on the y-terms:
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x^2+3x + (3/2)^2 + y^2 - 2y + 1 = 2 + (3/2)^2 + 1
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Factor and simplify:
(x+(3/2))^2 + (y-1)^2 = 21/4
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Center: (-3/2 , 1)
Radius: (1/2)sqrt(21)
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Cheers,
Stan H.
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