Question

The equation of line AB is (y−3) = 5 (x − 4). What is the slope of a line perpendicular to line AB?

−5
5
-1/5
1/5

Answer 1

The perpendicular slope would be -1/5.

Explanation:

This is because we can locate the slope of the original line as 5 (the number just outside of the x-coordinate parenthesis.

Then we know that perpendicular lines have opposite and reciprocal slopes. So we take the 5 and change the sign (-5), then we flip it (-1/5).