SOLUTION: Find the center and radius of the circle with equation, 3x2 + 3y2 - 21x + 6 y + 7 = 0

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Question 974306: Find the center and radius of the circle with equation,
3x2 + 3y2 - 21x + 6 y + 7 = 0
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
3x2 + 3y2 - 21x + 6 y + 7 = 0 ?

3x^2 + 3y^2 - 21x + 6 y + 7 = 0

3x%5E2+%2B+3y%5E2+-+21x+%2B+6+y+%2B+7+=+0
3x%5E2-21x%2B3y%5E2%2B6y%2B7=0
3%28x%5E2-7y%29%2B3%28y%5E2%2B2y%29%2B7=0
Complete The Squares:
3%28x%5E2-7y%2B%287%2F2%29%5E2%29%2B3%28y%5E2%2B2y%2B1%29%2B7=3%2849%2F4%29%2B3
3%28x-7%2F2%29%5E2%2B3%28y%2B1%29%5E2%2B7=3%2849%2F4%29%2B3
%28x-7%2F2%29%5E2%2B%28y%2B1%29%5E2%2B7%2F3=49%2F4%2B1
%28x-7%2F2%29%5E2%2B%28y%2B1%29%5E2=49%2F4%2B1-7%2F3
RHS is %2849%2A%283%29%2B12-7%284%29%29%2F12
131%2F12
10%2611%2F12

highlight%28%28x-7%2F2%29%5E2%2B%28y%2B1%29%5E2=10%2611%2F12%29

Center is (7/2,-1) and radius seems to be sqrt%2810%2611%2F12%29 ---- might be computational mistake