Hello!
To solve this equation, lets put all the whole numbers on the right side, and the variables on the left by using inverse operations.
5x-13=8-2x
5x=21-2x
7x=21
x=3
Just to make sure this is correct, we will plug this value into the original equation.
15-13=8-6
2=2
This statement is true, so x=3.
I hope this helps!