SOLUTION: Find the radius of a circle with equation x^2 - 6x + y^2 + 10y = 2

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Question 809582: Find the radius of a circle with equation
x^2 - 6x + y^2 + 10y = 2
Answer by plastery(3) About Me  (Show Source):
You can put this solution on YOUR website!
%28x-x%5B0%5D%29%5E2%2B%28y-y%5B0%5D%29%5E2=r%5E2 this is the standard equation for a circonference with center at point (x%5B0%5D,y%5B0%5D) and radius r.
So let's try to put the given equation in standard form.
x%5E2-6x%2By%5E2%2B10y=2
x%5E2-2%2A3%2Ax%2By%5E2-2%2A%28-5%29%2Ay=2
x%5E2-2%2A3%2Ax%2B3%5E2-3%5E2%2By%5E2-2%2A%28-5%29%2Ay%2B%28-5%29%5E2-%28-5%29%5E2=2
x%5E2-2%2A3%2Ax%2B3%5E2%2By%5E2-2%2A%28-5%29%2Ay%2B%28-5%29%5E2=2%2B3%5E2%2B%28-5%29%5E2
%28x-3%29%5E2%2B%28y-%28-5%29%29%5E2=2%2B3%5E2%2B%28-5%29%5E2
%28x-3%29%5E2%2B%28y-%28-5%29%29%5E2=2%2B9%2B25
%28x-3%29%5E2%2B%28y-%28-5%29%29%5E2=36
%28x-3%29%5E2%2B%28y-%28-5%29%29%5E2=6%5E2
Therefore the given equation stands for a circonference with center in (3,-5) and radius 6