Notice that p times V will always give you a constant when you're talking about the same temperature and the same number of mole. So if I have one set of conditions p one times v one, that will give me a constant. And if I have the second set of conditions p two times v two, it will give me the same constant, right? So I can set them equal. This guy is equal to the same constant that this number represents. So this is my equation for two sets of data or two sets of conditions.