SOLUTION: Solve. (x+2)(x-11)(x+1)>0 The solution set is {x|___}

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Question 240634: Solve.
(x+2)(x-11)(x+1)>0
The solution set is {x|___}
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
Are you allowed to use a graphing calculator or graphing techniques???

If so, then sketch y=(x+2)(x-11)(x+1).

This graph has zeros at x=-2, x=11, and x=-1. Sketch the graph using x values (based upon the zeros that you just found!) from x=-5 to x = 15. Values of y must be larger, but you can try using values from -100 to 100. I'll use the algebra.com calculator and see what it looks like:
graph%28300%2C300%2C-5%2C15%2C-100%2C100%2C+%28x%2B2%29%28x-11%29%28x%2B1%29%29

Now, since you are solving the inequality (x+2)(x-11)(x+1)>0, you need to find all values of x for which the graph y=(x+2)(x-11)(x+1) are ABOVE the x axis.

This would be values of x from -2 to -1 or values of x from 11 to infinity.
{x|-2 < x <-1} U {x|x > 11}

Dr. Robert J. Rapalje, Retired
Seminole State College of Florida