## College Algebra (10th Edition)

$\color{blue}{x=4}$
RECALL: A vertical line has an undefined slope and an equation of the form $x=h$ where $h$ is the x-intercept. All points on the line have $x=h$. The given line is vertical and contains the point $(4, -5)$. This means that all points on the line have $x=4$, and that the equation of the line itself is $x=4$. Thus, the equation of the line is: $\color{blue}{x=4}$