College Algebra 7th Edition

$x=-1$
RECALL: (1) A vertical line has an undefined slope and has an equation of the form $x=h$ where $h$ is the x-coordiante of all the points on the line. (2) Vertical lines are parallel to each other. The line we are looking for the equation if is parallel to the line $x=5$. $x=5$ is a vertical line so its slope is undefined. This means that the line we are looking for the equation of is also vertical and has an equation of the form $x=h$. The line passes through the point $(-1, 2)$. The x-coordinate of this point is $-1$. Therefore, the equation of the line we are looking for is: $x=-1$