This right here, that is this y value right over here. That is mx1 plus b. I don't want to get my graph too cluttered, so I'll just delete that there. That is error 1 right over there. That is error 1, and we want the squared errors between each of the points in the line. So that's the first one. Then you do the same thing for the second point. So we started our discussion this way, y2 minus mx2 plus b squared all the way, I'll do dot, dot, dot to show that there are a bunch of these that we have to do until we get to the nth point, all the way to yn minus mxn plus b squared.