SOLUTION: the roots of x3+x2-20x=0

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Question 331821: the roots of x3+x2-20x=0
Answer by jrfrunner(365) About Me  (Show Source):
You can put this solution on YOUR website!
the roots of x%5E3%2Bx%5E2-20x=0
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Since this is a polynomial of degree 3, there are 3 roots
Factor out the common x
x%5E3%2Bx%5E2-20x+=+x%2A%28x%5E2%2Bx-20%29+=+0
x%5E3%2Bx%5E2-20x+=+x%2A%28x%2B5%29%28x-4%29+=+0
x=0 , x=-5, x=4