Question

DO NOW: Slopes of ZERO and slopes that are UNDEFINED look very similar. What is the difference between the way those slopes look in fraction form?

Answer 1

The slope of a line that passes through points (x1, y1) and (x2, y2) is:

$m=\frac{y_2-y_1}{x_2-x_1}$

When the numerator is equal to zero, the slope is equal to zero.

When the denominator is equal to zero, the slope is undefined (you can't divide by zero).