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

##### 1 Answer
Jul 1, 2016

Slope of line perpendicular to $x + 3 y = 5$ is $3$

#### Explanation:

The product of slopes of two lines perpendicular to each other is $- 1$.

To find the slope of line $x + 3 y = 5$, let us convert it into slope intercept from $y = m x + c$, where $m$ is the slope of line and $c$ is its intercept on $y$-axis.

As $x + 3 y = 5$, we have $3 y = - x + 5$ or

$y = - \frac{1}{3} x + \frac{5}{3}$

Hence slope of $x + 3 y = 5$ is $- \frac{1}{3}$ and

slope of line perpendicular to it will be $\frac{- 1}{- \frac{1}{3}} = \frac{1}{\frac{1}{3}} = 3$