Solve 7x - 14 = 4x + 7

Like all equations, you're going to start off by getting all the x's on the same side of the = side and all the rest on the other side. So we start off with 7x-14=4x+7. Moving the x's to one side means that we have to subtract 4x from both sides, which means we end up with 7x-4x-14=4x-4x+7 which is 3x-14=7. Then we move all the rest to the right hand side which means adding 14 to both sides, ending up with 3x=21. The last step is to divide by 3 to get the 3x to change into x (which is 1x). This  means we end up with x=7.