Find an equation of the line passing through each of the following pairs of points.
(−3, 9), (−3, −5)
slope = (-5 - 9)/(-3 + 3) = -14/0
Ahhh, so the line is vertical, notice the x values are the same for both points.
it's equation would simply be x = -3
(Any vertical line has the form x = c , and any horizontal line will have the form y = k , just look at the x or y values of the points to state c or k)