Question

How to represent and solve equations with variables on both sides

Answer 1

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

Answer 2

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
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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)

                  
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