How do you find the slope that is perpendicular to the line #y = 4x + 5#?

1 Answer
Feb 3, 2017

Answer:

The slope of a perpendicular line will be #-1/4#

Explanation:

This equation is in slope-intercept form which is: #y = color(red)(m)x + color(blue)(b)#

Where #color(red)(m)# is the slope and #color(blue)(b)# is the y-intercept value.

Therefore we know the slope of this line is #color(red)(m = 4)#

A line perpendicular to this line will have a slope (let's call it #color(blue)(m_p)#) the negative inverse of the slope of the line given in the problem. Or #color(blue)(m_p) = -1/color(red)(m)#

Substituting the slope we found above gives:

#color(blue)(m_p) = -1/color(red)(4)#