SOLUTION: I really need help, I am an adult struggling with algebra. I have a very hard time starting out the problem. This specific problem I need to find the x intercept of y = x^3-

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Question 64321This question is from textbook college algebra
: I really need help, I am an adult struggling with algebra. I have a very hard time starting out the problem. This specific problem I need to find the x intercept of

y = x^3-2x^2-8x
I think this is how I would start the problem
(x^2-4) (x+2)
and then foil it but I really am stuck.... Please help me thank you. This question is from textbook college algebra

Answer by 303795(602) About Me  (Show Source):
You can put this solution on YOUR website!
The x intercept is where the value of y is 0 so you are trying to solve
0+=+x%5E3-2x%5E2-8x
Factorise by taking out a common factor of x
0+=+x%28x%5E2-2x-8%29
Factorise the trinomial by finding two numbers with a sum of -2 and a product of -8
0+=+x%28x-4%29%28x%2B2%29
To get an answer of 0 one of the numbers multiplied together must be 0.
So either x = 0 or x-4=0 or x+2=0
So the y intercepts are 0,4 and -2