Question 391197
If a linear equation is vertical, then its slope is undefined. The only way for {{{DELTA(y)/DELTA(x)}}} (the expression for slope) to be undefined is if there is some {{{DELTA(y)}}} such that {{{DELTA(x) = 0}}}. This means that for some change in y, x is held constant. Since the line goes through (-4, 8), then x is held constant at -4. Therefore the equation is x = -4.