SOLUTION: Give the coordinates of the center and find the radius. 9x^2+9y^2-12y=5

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Question 913599: Give the coordinates of the center and find the radius.
9x^2+9y^2-12y=5
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
9x%5E2%2B9%28y%5E2-%284%2F3%29y%29=5
9x%5E2%2B9%28y%5E2-%284%2F3%29y%2B%282%2F3%29%5E2-%282%2F3%29%5E2%29=5, completing the square for y
9x%5E2%2B9%28%28y-2%2F3%29%5E2-4%2F9%29=5
9x%5E2%2B9%28y-2%2F3%29%5E2-4=5
9x%5E2%2B9%28y-2%2F3%29%5E2=9
Divide both members by 9.
x%5E2%2B%28y-2%2F3%29%5E2=9=3%5E2

Radius is 3;
Center is (0, 2/3)