# How to find the slope of a perpendicular line?

#### Understand the Problem

The question is asking how to calculate the slope of a line that is perpendicular to another line. To find this, we need to understand that if we have the slope of one line, the slope of a perpendicular line can be determined using the negative reciprocal of the original slope.

-\frac{1}{m}

The slope of the perpendicular line is the negative reciprocal of the original slope, $-\frac{1}{m}$.

#### Steps to Solve

1. Identify the slope of the given line

First, find the slope of the original line. The slope is often represented by $m$ and can be found if the equation of the line is given in the slope-intercept form $y = mx + b$. If the line equation is in a different form, you may need to convert it first.

1. Find the negative reciprocal of the slope

The slope of a line perpendicular to the original line is the negative reciprocal of the original slope $m$. This means if the slope of the original line is $m$, then the slope $m'$ of the perpendicular line is $-\frac{1}{m}$.

1. Combine the results

State the final result clearly after calculating the negative reciprocal.

The slope of the perpendicular line is the negative reciprocal of the original slope, $-\frac{1}{m}$.