SOLUTION: how do i factor the trinomial -x^2 - 11X + 180

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Question 591991: how do i factor the trinomial -x^2 - 11X + 180
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+-x%5E2+-+11x+%2B+180+
Use quadratic formula
+x+=+%28-b+%2B-+sqrt%28+b%5E2+-+4%2Aa%2Ac+%29%29+%2F+%282%2Aa%29+
+a+=+-1+
+b+=+-11+
+c+=+180+
+x+=+%28-b+%2B-+sqrt%28+b%5E2+-+4%2Aa%2Ac+%29%29+%2F+%282%2Aa%29+

+x+=+%28+11+%2B-+sqrt%28+121+%2B+720+%29%29+%2F+%28-2+%29+
+x+=+%28+11+%2B-+sqrt%28+841+%29%29+%2F+%28-2+%29+
+x+=+%28+11+%2B+29+%29+%2F+%28-2+%29+
+x+=+40%2F%28-2%29+
+x+=+-20+
and
+x+=+%28+11+-+29+%29+%2F+%28-2%29+
+x+=+%28-18%29+%2F+%28-2%29+
+x+=+9+
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Rewriting the answers,
+-x+-+20+=+0+
+x+-+9+=+0+
+%28-+x+-+20+%29%2A%28+x+-+9+%29+=++-x%5E2+-+20x+%2B+9x+%2B+180+
+%28-+x+-+20+%29%2A%28+x+-+9+%29+=++-x%5E2+-+11x+%2B+180+