We derived the least-squares estimate of the slope in two different forms. Show that it can also be written as where r = is the Pearson's correlation coefficient, Sx are the means. 1 n-1. n are the standard deviations, and i=1 1 (9(5) n-1 Sx Sy B X = n 1 Syr. Sx i=1 (x - x) and. = Sy n x-12-9-1 xi and y = n. 1 n-1. n i=1 Yi n i=1 (y - y)