SOLUTION: Algebra 2: Write an equation of a circle with center (-2,-3) and radius 8.

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Question 827709: Algebra 2: Write an equation of a circle with center (-2,-3) and radius 8.
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
OQ=x-%28-2%29 , PQ=y-%28-3%29 , and OP=8
According to the Pythagorean theorem for right triangle OPQ, OQ%5E2%2BPQ%5E2=OP%5E2 so
%28x-%28-2%29%29%5E2%2B%28y-%28-3%29%29%5E2=8%5E2
highlight%28%28x%2B2%29%5E2%2B%28y%2B3%29%5E2=64%29 or we can transform it:
x%5E2%2B4x%2B4%2By%5E2%2B6y%2B9=64
x%5E2%2By%5E2%2B4x%2B6y%2B13=64
x%5E2%2By%5E2%2B4x%2B6y%2B13-64=0
highlight%28x%5E2%2By%5E2%2B4x%2B6y-21=0%29