Consider the line -4x-8y=6.

What is the slope of a line parallel to this line?

What is the slope of a line perpendicular to this line?

1 answer

rewrite as
8y = -4x+6
y = -1/2 x + 3/4

so, y and all parallel lines have slope m = -1/2

all perpendicular lines have slope -1/m = -1/(-1/2) = +2