SOLUTION: i need to find and equation for the circle it had a center(3,0) and has a radius of 9

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Question 49718: i need to find and equation for the circle it had a center(3,0) and has a radius of 9
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
A circle with center at (h,k) and radius r has the equation %28x-h%29%5E2+%2B%28y-k%29%5E2+=+r%5E2

Therefore, if center is (3,0) and radius 9, then the equation is +%28x-3%29%5E2+%2By%5E2+=+9%5E2

This could also be written as
+x%5E2+-+6x+%2B+9+%2B+y%5E2+=+81 or
+x%5E2+%2By%5E2+-+6x+-72+=+0

I personally like the first form: +%28x-3%29%5E2+%2By%5E2+=+81


R^2 at SCC