First, it is important to understand that any equation that is x=some number is just a vertical line that hits the x-axis at the given number. For example, x=-2 would be a vertical line hitting the x-axis at -2. Therefore, the line we are trying to identify would also be vertical (and have the form x=some number) because we know the lines are parallel. Then, since we're given the point (-5,4), we know the line needs to hit the x-axis at -5, therefore the equation would be x=-5.
I hope this helps.
