help me solve

6/z+8 = 5/z-3?
do i first find the lcd?

2 answers

I will assume that you mean
6/(z+8) = 5/(z-3)
Parentheses are very important when you write equations on a single line, as here.

Cross multiply to get
6z - 18 = 5z + 40
Now combine terms
z = 58

You could look for an LCM, but that step is not necessary. The answer would be the same.
Maybe I wrote the problem wrong...
6 = 5
z+8 4+x

is that the same as what i put earlier?