So that's this expanded out. And now if we want to x minus 4, or 4 minus x times 4 minus x. So if we just have 4 minus x times 4 minus x. We could actually do it this way as well. But that's just going to be 4 times 4, which is 16. Plus 4 times negative x, which is negative 4x. Negative x times 4, another negative 4x.