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Answer:
Step-by-step explanation:
The formula of a slope:
[tex]m=\dfrac{y_2-y_1}{x_2-x_1}[/tex]
We have the points (5, 8) and (5, 7). Substitute:
[tex]m=\dfrac{7-8}{5-5}=\dfrac{-1}{0}[/tex]
Dividing by zero is not possible!
Therefore the slope is undefined.