SOLUTION: How is x-5 a factor of the polynomial x^2-x-20? I know that x-5 is the answer but I have no idea how to do this.
Thanks for your help,
Sarah
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-> SOLUTION: How is x-5 a factor of the polynomial x^2-x-20? I know that x-5 is the answer but I have no idea how to do this.
Thanks for your help,
Sarah
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Question 436468: How is x-5 a factor of the polynomial x^2-x-20? I know that x-5 is the answer but I have no idea how to do this.
Thanks for your help,
Sarah Answer by robertb(5830) (Show Source):
You can put this solution on YOUR website! Solve x - 5 = 0, or x = 5. Then substitute into the equation:
, so 5 is a root. Then by the factor theorem (if a is a root then x - a is a factor), x - 5 is a factor.
