# Math Help - Solving Rational Inequalities

1. ## Solving Rational Inequalities

Solve this inequality: 5/6x+2/3x>3/4.
So I simplified the left side and got 3/2x, then moved the equation to one side and got 3/2x-3/4>0. I got x>1/2, but the answer is wrong.
Can somebody help me?

2. ## Re: Solving Rational Inequalities

Lets see your work. How did you get x>1/2 , from 3/2x-3/4>0 ?

3. ## Re: Solving Rational Inequalities

3/2x>3/4. Then, I divided both sides by 3/2.

4. ## Re: Solving Rational Inequalities

That gives (1/x) > (1/2) .

5. ## Re: Solving Rational Inequalities

How did you get that?

6. ## Re: Solving Rational Inequalities

Using algebra ... and assuming what you meant was 3/(2x) > 3/4 .

Was the original problem: Solve 5/(6x) + 2/(3x) > 3/4 ?

Yes

8. ## Re: Solving Rational Inequalities

Originally Posted by SammyS
Using algebra ... and assuming what you meant was 3/(2x) > 3/4 .

Was the original problem: Solve 5/(6x) + 2/(3x) > 3/4 ?
Originally Posted by Dragon08
Yes
Starting with     $\frac{3}{2x}>\frac{3}{4}$

Multiply by 2/3    $\frac{2}{3}\cdot\frac{3}{2x}>\frac{2}{3}\cdot\frac {3}{4}$

This gives       $\frac{1}{x}>\frac{1}{2}$

Then a little known rule says that if   $\frac{a}{b}>\frac{c}{d}$ then   $\frac{b}{a}<\frac{d}{c}$

9. ## Re: Solving Rational Inequalities

Okay, I get it. Thank you

10. ## Re: Solving Rational Inequalities

Originally Posted by Dragon08
Solve this inequality: 5/6x+2/3x>3/4.
So I simplified the left side and got 3/2x, then moved the equation to one side and got 3/2x-3/4>0. I got x>1/2, but the answer is wrong.
Can somebody help me?