Firstly, you need to understand that the two equations are interlinked, therefore the x and the y variables are the same values in both equations. To make things easier, we can number both equations. What we are trying to do is eliminate one of the variables to allow us to solve an equation. We can do this by multiplying equation one by 2. This gives 10x+6=6y. Now both equations have 6y in. Now we can take equation 2 away from the new equation 1. This gives x-3=0, which can then be solved to show x=3. This can then be plugged back into either of the original formulae to find y. y=6.