SOLUTION: Solve. Factor by graphing. x^3+5x^2-x-5=0

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Question 957676: Solve. Factor by graphing.
x^3+5x^2-x-5=0
Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
I think you meant "Factor by GROUPing, not "GRAPHing".

x%5E3%2B5x%5E2-x-5%22%22=%22%22%220%22

Factor x2 out of the first two terms and get x2(x+5)
Factor -1 out of the last two terms and get -1(x+5)

x%5E2red%28%28x%2B5%29%29-1red%28%28x%2B5%29%29%22%22=%22%22%220%22

There is a common factor (x+5) so factor it out:

red%28%28x%2B5%29%29%28x%5E2-1%29%22%22=%22%22%220%22

Factor x2-1 as (x-1)(x+1)

red%28%28x%2B5%29%29%28x-1%29%28x%2B1%29%22%22=%22%22%220%22

Set each factor = 0 and get

x+5 = 0,  x-1 = 0,  x+1 = 0
  x = -5,   x = 1     x = -1

Edwin