SOLUTION: Find the equation of the circle with center at the origin and x-intercepts 9 and -9

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Question 1153875: Find the equation of the circle with center at the origin and x-intercepts 9 and -9
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+%28+x+-+h+%29%5E2+%2B+%28+y+-+k+%29%5E2+=+r%5E2+
( h, k ) = ( 0,0 )
The circle goes through ( 9, 0 ) and ( -9, 0 )
+%28+x+-+0+%29%5E2+%2B+%28+y+-+0+%29%5E2+=+r%5E2%0D%0A%7B%7B%7B+x%5E2+%2B+y%5E2+=+r%5E2+
+9%5E2+%2B+0%5E2+=+r%5E2+
+r+=+9+
The equation is:
+x%5E2+%2B+y%5E2+=+9+