SOLUTION: x²+y²+8x+8y=0

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Question 1175397: x²+y²+8x+8y=0
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
What about it?

x%5E2%2B8x%2By%5E2%2B8y=0
x%5E2%2B8x%2B16%2By%5E2%2B8y%2B16=16%2B16
%28x%2B4%29%5E2%2B%28y%2B4%29%5E2=32----------------circle centered at (-4,-4) and radius sqrt%2832%29.

Answer by ikleyn(52788) About Me  (Show Source):
You can put this solution on YOUR website!
.

    x² + y² + 8x + 8y = 0


    (x^2 + 8x) + (y^2 + 8y) = 


    (x*2 + 8x + 16) + (y^2 + 8y + 16) = 16 + 16


Make a square


    %28x%2B4%29%5E2 + %28y%2B4%29%5E2 = 32


It is the standard equation of the circle centered at the point (-4,-4) with the radius of  sqrt%2832%29 = 4%2Asqrt%282%29 units.

Solved.