SOLUTION: Write the polynomial in factored form. x3 – 3x2 – 10x

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Question 693322: Write the polynomial in factored form.
x3 – 3x2 – 10x
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+x%5E3+%96+3x%5E2+%96+10x+
Factor out +x+
+x%2A%28+x%5E2+-+3x+-+10+%29+
+x%2A%28+x+-+5+%29%2A%28+x+%2B+2+%29+ ( I could see this by inspection )
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If you need a method, use the quadratic formula
+x+=+%28-b+%2B-+sqrt%28+b%5E2+-+4%2Aa%2Ac+%29%29+%2F+%282%2Aa%29+
+a+=+1+
+b+=+-3+
+c+=+-10+
+x+=+%28-%28-3%29+%2B-+sqrt%28+%28-3%29%5E2+-+4%2A1%2A%28-10%29+%29%29+%2F+%282%2A1%29+
+x+=+%28+3+%2B-+sqrt%28+9+%2B+40+%29%29+%2F+2+
+x+=+%28+3+%2B-+sqrt%28+49+%29%29+%2F+2+
+x+=+%28+3+%2B+7%29+%2F+2+
+x+=+5+
and, also
+x+=+%28+3+-+7%29+%2F+2+
+x+=+-2+
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Rewriting these roots,
+x+-+5+=+0+
+x+%2B+2+=+0+
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So I get
+x%2A%28+x+-+5+%29%2A%28+x+%2B+2+%29+
OK