We will use the two point slope form formula. Which looks like this:
[tex]m = \frac{y_{2} - y_{1}}{x_{2} - x_{1}}
[/tex]
Then plug in the values.
[tex]m = \frac{3 - 3}{20 - 19} [/tex]
Solve.
[tex]m = \frac{0}{1} [/tex]
Because the numerator is 0, it means the the fraction is equal to 0. Thus, the slope is 0.
