Hi, A line contains (1,y),(4,5),(2,-1),and (x,3) | m being the Slope fo this line (4,5) (2,-1) m = 6/2 = 3 (4,5) (1,y) (5-y)/3 = 3 or 5-y = 9 and y = -4 (4,5) (x,3) 2/(4-x) = 3 or 4-x = 2/3 and x = 4-2/3 = 3 1/3