# What is the slope of 2x = -8?

$x = - 4$
There is no finite answer. The slope is $\infty$ because $\Delta y$ goes from $- \infty$ to $\infty$, even when $\Delta x = 0$. That means $\Delta y = \infty$.
$\frac{\Delta y}{\Delta x} = \frac{\infty}{0} = \infty \cdot \frac{1}{0} = \infty \cdot \infty = \infty$
Imagine a line of slope 1 ($y = x$). Now imagine the slope increasing towards $\infty$. That would mean the line rotates counterclockwise until it becomes perfectly vertical. That is the line $x = a$. Here, $a = - 4$.