How do you know when to move the number to the left or the right.
For example
(x-5)/(x+8)=5/7 or
(y-2)/(y+2)=3/7
I know the first problems answer is 2/75 and the second is 5 and in both cases I seem to mess up on the last part of moving the numbers like for instance in the 2/75 I first had the answer of 75/2 I had the numbers right but the wrong placement and the same with the other I first had 4/20 instead of 20/4 which equals 5 so I need to know how do you know which way to move the number to the left or the right?