SOLUTION: Find an equation of the circle that has center −1,2 and passes through −5,6.

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Question 1087291: Find an equation of the circle that has center −1,2 and passes through −5,6.
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
equation of the circle is:
%28x-h%29%5E2%2B%28y-k%29%5E2=r%5E2 where h and k are coordinates of the center, and r is a radius
if a circle has center (-1,2), means h=-1 and k=2
so far we have:
%28x-%28-1%29%29%5E2%2B%28y-2%29%5E2=r%5E2
%28x%2B1%29%5E2%2B%28y-2%29%5E2=r%5E2
and if passes through (-5,6), use it to find r
%28-5%2B1%29%5E2%2B%286-2%29%5E2=r%5E2
%28-4%29%5E2%2B%284%29%5E2=r%5E2
16%2B16=r%5E2
r%5E2=32
so, your equation is:
%28x%2B1%29%5E2%2B%28y-2%29%5E2=32