Question

What is the slope of a line perpendicular to the line whose equation is 12x-9y=135

Answer 1

`(-9)/(12)`

Explanation:

First, we need to isolate y.

1. Subtract 12x from both sides.

-9y=-12x+135

2. Divide by -9 in order to isolate y.

`y=(12)/(9) x-15`

3. Understand that perpendicular equations' slopes are opposite and reciprocal to the original equation. The slope of the original equation is
`(12)/(9)`, so the reciprocal and opposite (flip and change the sign) slope would be
`(-9)/(12)`.