# How do you find the slope that is perpendicular to the line y = 3/5x - 8?

Jun 17, 2016

Slope of perpendicular: $\textcolor{g r e e n}{- \frac{5}{3}}$
If a line has a slope of $\textcolor{g r e e n}{m}$ then all lines perpendicular to it have a slope of $\textcolor{g r e e n}{- \frac{1}{m}}$
$y = \textcolor{g r e e n}{\frac{3}{5}} x - 8$ is in slope-intercept form with a slope of $\textcolor{g r e e n}{m = \frac{3}{5}}$
Therefore any line perpendicular to $y = \frac{3}{5} x - 8$ has a slope of:
$\textcolor{w h i t e}{\text{XXX}} - \frac{1}{\frac{3}{5}} = - \frac{5}{3}$