Well, we have n of these lines, right? This is the first line, second line, then a bunch, bunch, bunch, all the way to the nth line. So we have b squared added to itself n times. So this right over here is just b squared n times. So we'll just write that as plus n times b squared. Now it doesn't look like, let me remind ourselves what this is all about. This is all just algebraic manipulation of the squared error between those n points and the line y equals mx plus b.