# Math Help - simplify

1. ## simplify

2/3 - 3/4 div.by 5/8 + 2/3
do i need to find a common denominator for the first two fractions as ell as the next two i have not done this in a while just need to remember can you show me?

2. (2/3 - 3/4)
(5/8 + 2/3)

first lets do what is inside the parentheses (you must find a common denominator in this case 12.

(2/3 - 3/4) = (8/12 - 9/12) = -(1/12)

(5/8 + 2/3) = (15/24 + 16/24) = -(1/24)

So now we have:

-(1/12)
-(1/24)

the negatives cancel.

(1/12)
(1/24)

and we can cross multiply

1.....24....24
-- * -- = ---
12....1.....12