Question

determine if the line containing points a and b is perpendicular, parallel or neither to the line containing points c and d.

a (4,-3), b (5,1), c (2,4),d (3,8)

Answer 1

line a-b described by : (1- (-3))/(5-4) = 4 (your slope)
line c-d: (8-4)/(3-2) = 4
so, both lines have the same slope, which means that lines are parallel

Answer 2

thanks