Since we're not dividing it by n, this is the mean times n. And then this is obviously, we don't have to simplify anything. So let's rewrite everything using our new notation, knowing that these are the means of these, you know, of y squared, of xy and all of that. So our squared error of the line, our squared error to the line, from the sum of the squared error to the line from the end points is going to equal to, this term right here is n, let me color code it a little bit. This term right here is n times the mean of the y squared values. This term right here is, I'll do it all in this green color, is equal to negative 2m, that's just that right there, times n times the mean of the xy values, the arithmetic mean. And then we have this term over here. I think you can appreciate this is simplifying the algebraic expression a good bit.