To find the slope of line $BC$, where $B = (-2,3)$ and $C = (-2,2)$, we use the slope formula:

$\text{slope} = \frac{y_2 - y_1}{x_2 - x_1}$

Substituting the coordinates of points $B$ and $C$:

$\text{slope of } BC = \frac{2 - 3}{-2 - (-2)} = \frac{-1}{0}$

Since the denominator is 0, the slope is undefined. This indicates that line $BC$ is a vertical line.

Would you like more details or have any questions about this?

Here are five related questions you might find helpful:

1. What does it mean for a line to have an undefined slope?
2. How do you identify if a line is vertical or horizontal from its slope?
3. What is the equation of a vertical line passing through point $B$?
4. How does the slope formula change for horizontal lines?
5. Can two different points on the same vertical line have the same slope?

Tip: A vertical line always has an undefined slope because the change in $x$ is zero, which results in division by zero.