SOLUTION: Find the radius and center of the circle with equation: 2x^(2)+2y^(2)+24x-81=0

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Question 1172348: Find the radius and center of the circle with equation:
2x^(2)+2y^(2)+24x-81=0
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
rewrite as
2x^2+24x+2y^2=81
divide by 2
x^2+12x+y^2=(81/2)
complete the square
x^2+12x+36+y^2=76.5
(x+6)^2+(y+0)^2=76.5
center is at (-6, 0) with radius sqrt(76.5);this is also 1.5 *sqrt(34)