# college algebra

posted by .

Solve the following inequality.

x^3+9x^2-108 less or equal to 0.
Then write your solution in interval notation. I am sooo confused and do not have any idea how to do this. Can someone please show me step by step please???

Thanks in advance. Someone who is confused.

• college algebra -

This polynomial graphing might help sometimes:
http://mathportal.org/calculators/polynomials-solvers/polynomial-graphing-calculator.php

zeros at x = -6 (double zero) and x = +3
so we really have
(x+6)(x+6)(x-3)

It is negative for large negative x
it comes up and bounces off the x axis at x=-6, dropping down negative again
it does not actually come up and cross the x axis until x = 3
from then on it is positive,
therefore negative for
x</= +3 except for touching zero at x = -6

## Similar Questions

1. ### Algebra

Just wondering if I did this correctly step by step. If not corrections are mostly appreciated! Solve the inequality and write the solution set in interval notation. Show work/explanation. (x+8)/(x-1) >= 0 8+x/x-1=1+9/x-1 9/x-1>=-1 …
2. ### Solve Inequality

Solve the inequality. Express your solution using interval notation and please show all of your work. x(x + 6)(8 – x) >= 0 I need help, I guess I'm not understanding the interval notation portion. I know, that when 0 <= x <= …
3. ### precalculus

solve the inequality algebraically. write the solution in interval notation. the absolute value of x-2/3 is less than or equal to 4
4. ### algebra

Solve the following inequality and write your answer using interval notation . Please show all your work 10^3 + 6x^2 - 90x - 54 < 0
5. ### algebra

Solve the following inequality and write answer using interval notation. Please show all of your work. 2x-5/3x^4-x^3+275x-125>=0
6. ### college algebra

solve the following inequality. write the answer in interval notation x^3-4x^2-21x<0 please show work so i can understand this problem better! thanks
7. ### calculus

solve the following inequality. write your solution in interval notation. x^3+9x^2-108 less than or equal to 0
8. ### calculus

solve the following inequality. write your solution in interval notation. x^3+9x^2-108 less than or equal to 0 please show all work