Question

What is the slope of a line perpendicular to x - 3y = 9?

Answer 1

First, let's convert this into slope-intercept form.

\(\Large \color{Black}{\Rightarrow -3y = -x + 9}\)

\(\Large \color{Black}{\Rightarrow y = {(x + 9) \over -3} }\)

\(\Large \color{Black}{\Rightarrow y = {-1 \over 3} }\)

\(\Large \color{Black}{\Rightarrow y = -{x \over 3} - 3 }\)

Slope is -1/3.
Slope of a line perpendicular to that would be the negative reciprocal.
-3/-1
3

Answer 2

3 is the slope of the perpendicular line.

Answer 3

whats a negative reciprocal?