We want to solve for n. The first step is to make 2n stand alone on the left hand side of the equation. This is achieved by subtracting 4 from the left hand side and the right hand side of the equation. It becomes
2n + 4 - 4=12 - 4
2n = 8
The next step is to divide the left hand side and the right hand side of the equation by 2. It becomes
