SOLUTION: find the value of k so that x^2+y^2+4x-6y+k=0 is the equation of circle of radius 5

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Question 1008225: find the value of k so that x^2+y^2+4x-6y+k=0 is the equation of circle of radius 5
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B4x%2By%5E2-6y=-k
x%5E2%2B4x%2B4%2By%5E2-6y%2B9=-k%2B4%2B9
%28x%2B2%29%5E2%2B%28y-3%29%5E2=13-k

Radius of 5 means radius squared is 25;
13-k=25
-k=25-13
highlight%28k=-12%29