SOLUTION: -2x-99+x^2

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Question 960057: -2x-99+x^2
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+-2x+-+99+%2B+x%5E2+
I'm guessing you want the roots
+x%5E2+-+2x+-+99+=+0+
Complete the square
+x%5E2+-+2x++%2B+%28+2%2F2%29%5E2+=+99+%2B+%28+2%2F2+%29%5E2+
+x%5E2+-+2x+%2B+1+=+99+%2B+1+
+%28+x+-+1+%29%5E2+=+10%5E2+
Take the square root of both sides
+x+-+1+=+10+
+x+=+11+
and, take the negative square root of +10+,
+x+-+1+=+-10+
+x+=+-9+
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+x+=+11 and
+x+=+-9+ are the roots
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check:
+%28+x+%2B+9+%29%2A%28+x+-+11+%29+=+0+
+x%5E2+-+2x+-+99+=+0+
OK