SOLUTION: Find the equation of a circle: center(-2,0):passes through(2,0)

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Question 262828: Find the equation of a circle: center(-2,0):passes through(2,0)
Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
The equation of a circle can be expressed as
%28x-h%29%5E2+%2B+%28y-k%29%5E2+=+r%5E2
we know the center, so we have
%28x%2B2%29%5E2+%2B+%28y%29%5E2+=+r%5E2
the distance from the center to the point on the circle is 4. This is also called radius. SO, we get
%28x%2B2%29%5E2+%2B+%28y%29%5E2+=+4%5E2