SOLUTION: how to find the radius and center of 25x^2+25y^2-20x+30y+13=0

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Question 1101114: how to find the radius and center of 25x^2+25y^2-20x+30y+13=0
Found 2 solutions by josgarithmetic, Alan3354:
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
25%28x%5E2-4x%2F5%29%2B25%28y%5E2%2B6y%2F5%29=-13
25%28x%5E2-4x%2F5%2B16%2F100%29%2B25%28y%5E2%2B6y%2F5%2B36%2F100%29=-13%2B4%2B9
25%28x-4%2F10%29%5E2%2B25%28y%2B6%2F10%29%5E2=0
highlight%28%28x-2%2F5%29%5E2%2B%28y%2B3%2F5%29%5E2=0%29
This is not a circle, has no radius, but center is at (2/5, -3/5).

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
how to find the radius and center of 25x^2+25y^2-20x+30y+13=0
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Complete the squares of x & y separately
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25x%5E2%2B25y%5E2-20x%2B30y+=+-13
x%5E2+-+0.8x+%2B+y%5E2+%2B+0.6y+=+-0.52
x%5E2+-+0.8x+0.16+%2B+y%5E2+%2B+0.6y+%2B+0.09+=+-0.52%2B0.16%2B0.09
%28x+-+0.4%29%5E2+%2B+%28y+-++0.3%29%5E2+=+-0.27
The r^2 term is negative.
Not a circle.
Typo maybe?
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