# Simplifying Expression

• December 2nd 2012, 08:34 AM
kevindorward
Simplifying Expression
Attachment 26023

so i divide the 15 & 18 by 3 to get 5/6
R8 - (-4) = r12
Q(-4)-3 = Q(-7)

just wondered which went on top or bottom ?
am i right in saying that r12 goes on top cause the r8 is a positive power ?
• December 2nd 2012, 09:09 AM
topsquark
Re: Simplifying Expression
Quote:

Originally Posted by kevindorward
Attachment 26023

so i divide the 15 & 18 by 3 to get 5/6
R8 - (-4) = r12
Q(-4)-3 = Q(-7)

just wondered which went on top or bottom ?
am i right in saying that r12 goes on top cause the r8 is a positive power ?

Yes, positive exponents go up top and negative exponents go on the bottom.

Typically when I start a problem like this I put all exponents as positive. For example
$\frac{r^8q^{-3}}{r^{-4}q^5}}$

I put this as
$\frac{r^8r^4}{q^3q^{5}}$

Then I simplify.

-Dan