If two lines are perpendicular their slopes or gradients are negative reciprocals of each other:
5 -1/5
-4 1/4
1/2 -2
do you see the idea?
Also the two gradients will multiply to equal -1. You can use that as a check.
Write the gradient of the line perpendicular to the line with gradient.
(a) 5 , (b) 7 , (c) -4 , (d) -9 , (e) 1/2 , (f) -3/4 , (g) 3/8 , (h) -2/3
2 answers
Thank you John