SOLUTION: How do I solve this inequality?: x^3+5x^2-9x-45 is greater than and equal to 0

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Question 388277: How do I solve this inequality?:
x^3+5x^2-9x-45 is greater than and equal to 0

Answer by Jk22(389) About Me  (Show Source):
You can put this solution on YOUR website!
x^3+5x^2-9x-45=x^2(x+5) -9(x+5) by grouping

we have (x+5)(x^2-9) is the function.

Since the roots are simple, and that for x->-oo the function goes to negative values, we have :

the domain where the function is positive is : [-5;-3]U[3,+oo[
Solved by pluggable solver: Plot Any Inequality
Graphing function x%5E3%2B5x%5E2-9x-45%3E0:

graph%28+300%2C+300%2C+-10%2C+10%2C+-10%2C+10%2C+x%5E3%2B5x%5E2-9x-45%3E0+%29