So if I were to add up all of these terms right here, if I were to add up this column right over there, what do I get? Well it's going to be y1 squared plus y2 squared plus y all the way to yn squared. That's those terms right over there. So I'm going to have that. And then I'm going to have minus, you have this common 2m amongst all of these terms over here. So let me write that down. 2m here, 2m here, 2m here.