## College Algebra (10th Edition)

$x+3=0$
RECALL: A vertical line has an equation of the form $x=h$, where $h$ is the x-intercept. Every point on this line has an x-coordinate of $x=h$. The given line is vertical, so its equation is in the form $x=h$. The line passes through the point $(-3, 4)$. Since the x-coordinate of this point is $-3$, every point on the line has $x=-3$. Thus, the equation of the line is $x = -3$. This equation can be written as $x+3=0$.