# How do you find the slope of a line perpendicular to y=(-3x)?

$y = \left(- 3 x\right)$ has a slope of $\left(- 3\right)$
If a line has a slope of $m$, any line perpendicular to it has a slope of $\left(- \frac{1}{m}\right)$
Any line perpendicular to $y = \left(- 3 x\right)$ has a slope of $\frac{1}{3}$