# What is the slope of the line perpendicular to  y=-3x-7 ?

May 7, 2016

${m}_{2} = + \frac{1}{3}$

#### Explanation:

In $y = \textcolor{red}{- 3} x - 7$, the slope is $\textcolor{red}{- 3} .$

If two lines are perpendicular, then the one slope is the negative reciprocal of the other. ${m}_{1} \times {m}_{2} = - 1$

(In easy language, turn the slope upside down and change the sign)

So if ${m}_{1} = - \frac{3}{1} , \text{ }$then ${m}_{2} = + \frac{1}{3}$