SOLUTION: find the center and radius of the following circle. 9x2 + 12x + 9y2 - 18y - 23 =0

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: find the center and radius of the following circle. 9x2 + 12x + 9y2 - 18y - 23 =0      Log On


   

Question 236943: find the center and radius of the following circle.
9x2 + 12x + 9y2 - 18y - 23 =0
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
find the center and radius of the following circle.
9x2 + 12x + 9y2 - 18y - 23 =0
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9(x^2 + (4/3)x + (2/3)^2) + 9(y^2 - 2y + 1) = 23 +9(2/3)^2 + 9
9(x+(2/3))^2 + 9(y-1)^2 = 68
(x+(2/3)^2 + (y-1)^2 = 68/9
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Center: (-2/3 , 1)
Radius: (sqrt(68))/3 = (2/3)sqrt(17)
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Cheers,
Stan H.