How to represent and solve equations with variables on both sides

First, move all the variable numbers to one side. Then, just solve for the variable.

To solve equations with variables on both sides you have to "move" one of the variables to the other side. Which will look like this:
Example: 2x + 8 = 4x +2 
                -2x         -2x
                        8 = 2x + 2
Now all we do is solve normally. 
Example:  8 = 2x + 2
                 -2          -2
                  6 = 2x
                  2    2
                  3 = x
Now I recommend that you check your answer simply by substituting x for 3. 
2(3) + 8 = 4(3) + 2
14 = 14

There you go. The basic steps for doing this is: 
1. Move one of the variables to the other side
2. Two step equation solving
3. Substitute (Optional)