# What is the slope of the line perpendicular to  y=9/4-7 ?

May 31, 2018

$\text{perpendicular slope is undefined}$

#### Explanation:

$y = \frac{9}{4} - 7 = - \frac{19}{4}$

$y = - \frac{19}{4}$

$\text{is the equation of a horizontal line parallel to the x-axis}$
$\text{passing through all points in the plane with a }$
$\text{y-coordinate equal to } - \frac{19}{4}$

$\text{because it is a horizontal line it's slope } = 0$

$\text{and so a line perpendicular to it is vertical and }$
$\text{parallel to the y-axis with slope undefined}$