Perpendicular lines have slopes whose product is -1. The slope given in
y = 3x - 2
is -3.
The slope of the perpendicular line will be m, and m needs to satisfy the equation
3 * m = -1
Hence m = -1/3.
Our perpendicular line is thus
y = (-1/3)x + b
for some constant b.
We are told that the perpendicular line goes through the point (-9,5). If so, then the following must hold:
5 = (-1/3)(-9) + b
= 3 + b
b = 2
Ans: y = (-1/3)x + 2
