# How do you find the slope that is perpendicular to the line y = -3x + 4?

Aug 7, 2017

See a solution process below:

#### Explanation:

This equation is in slope-intercept form. The slope-intercept form of a linear equation is: $y = \textcolor{red}{m} x + \textcolor{b l u e}{b}$

Where $\textcolor{red}{m}$ is the slope and $\textcolor{b l u e}{b}$ is the y-intercept value.

Therefore, the slope of this line is: $\textcolor{red}{m} = - 3$

Let's call the slope of a perpendicular line: ${m}_{p}$

There formula for the slope of a perpendicular line is the negative inverse of the slope or:

${m}_{p} = - \frac{1}{m}$

Substituting for $m$ gives the slope of a perpendicular line as:

${m}_{p} = \frac{- 1}{-} 3 = \frac{1}{3}$