## anonymous one year ago SIMPLE EQUATION, PLEASE EXPLAIN? IT'S ALGEBRA

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1. anonymous

1 1/2r - 2/3r = -3/2 5/6 = -3/2 6/5 x 5/6r = 6/5 x -3/2 r = -9/5 and simplified that would be r = -1 4/5

2. anonymous

Did that help ? @HaperFink22

3. anonymous

@kenialove I don't know. My friend was telling me otherwise :\ I'm confused

4. jim_thompson5910

First convert the mixed number to an improper fraction $\Large 1 \frac{1}{2} = 1+\frac{1}{2}$ $\Large 1 \frac{1}{2} = 1*\color{red}{\frac{2}{2}}+\frac{1}{2}$ $\Large 1 \frac{1}{2} = \frac{2}{2}+\frac{1}{2}$ $\Large 1 \frac{1}{2} = \frac{2+1}{2}$ $\Large 1 \frac{1}{2} = \frac{3}{2}$ Hopefully all this makes sense?

5. anonymous

@jim_thompson5910 Could you please solve this expression specifically? It seems easy when I read your work but for some reason the problem above challenges me. :\

6. jim_thompson5910

do you see how 1 & 1/2 is equal to 3/2 ?

7. anonymous

@jim_thompson5910 Yes, but in this equation we're solving for r

8. jim_thompson5910

So $\Large 1 \frac{1}{2}r - \frac{2}{3}r = -\frac{3}{2}$ turns into $\Large \frac{3}{2}r - \frac{2}{3}r = -\frac{3}{2}$

9. jim_thompson5910

The LCD is 6. Multiply both sides by the LCD to clear out the fractions $\Large \frac{3}{2}r - \frac{2}{3}r = -\frac{3}{2}$ $\Large 6*\left(\frac{3}{2}r - \frac{2}{3}r\right) = 6*\left(-\frac{3}{2}\right)$ $\Large 6*\left(\frac{3}{2}r\right)+6*\left( - \frac{2}{3}r\right) = 6*\left(-\frac{3}{2}\right)$ $\Large 9r-4r = -9$ Now solve for r

10. anonymous

@jim_thompson5910 THANK YOU! That part with the LCD was what was confusing me so much. You subtract 9r - 4r which equals 5r. 5r = 9 r= 9/5

11. jim_thompson5910

you lost a negative

12. jim_thompson5910

it should be 5r = -9 and not 5r = 9

13. jim_thompson5910

but you have the right idea: divide both sides by 5 to get r = -9/5

14. anonymous

@jim_thompson5910 thanks for catching my mistake. I understand how this is done now :)

15. jim_thompson5910

I'm glad it makes more sense now