# Homework Help: Absolute value, what?

1. Aug 26, 2010

### andreynr6

Excuse me for my english;

Decide for all the x so this works out; ((2x-7)/(x3+3))<(9/x)<=x²-5x+9

where "<=" is the same as "and =".

Having some troubles getting the right values between (9/x)<=x²-5x+9, but otherwise it's fine..

hope you can help me!

2. Aug 26, 2010

### Mentallic

For future reference, please use the layout given to you when starting a thread in the homework help section, particularly the "attempt at a solution" part.

To find where $$x^2-5x+9\geq 9/x$$ if you multiply through by x2 (a positive number for all real non-zero x) you will end up with a quartic that can be factorized easily using the rational root theorem. It should be easy from there where it's greater than zero.

3. Aug 26, 2010

### Staff: Mentor

Sorry about that Mentallic. I moved his thread to Homework Help from a general math forum, and asked him to post more of his work. I should have posted a note here as well.

4. Aug 26, 2010

### Mentallic

Oh, no problem