# What is the slope of a line perpendicular to Ax+By+C=0?

##### 1 Answer

Jul 31, 2016

#Bx-Ay+C=0#

#### Explanation:

Given -

#Ax+By+C=0#

In such case you have to interchange the co-efficients of

The equation of the perpendicular line is

#Bx-Ay+C=0#

You can check it by using the formula

#m_1xxm_2=-1#

Slope of the first line -

#m_1=-a/b=-A/B#

Slope of the second line -

#m_2=-a/b=-B/(-A)=B/A#

Substituting these values in the formula

We get -

#-cancelA/cancelB xx cancelB/cancelA=-1#