# How do you find the slope of a line G(-3, 4) H(-3, -6)?

Considering your points I would say that you have a vertical line passing through $x = - 3$. Try defining the slope of a vertical line is difficult because the slope represents the change in $y$ for a change in $x$ or:
Slope=$m = \frac{\Delta y}{\Delta \left(x\right)} = \frac{- 6 - 4}{- 3 + 3} = - \frac{10}{0}$ that cannot be evaluated!