Answer: undefined
Explanation:
#1 use the horizontal and vertical line concept
- when the line is horizontal, the slope is 0
- when the line is vertical, the slope is undefined
- Thus, in this case, the line is vertical, the slope is undefined.
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# use the slope formula

- the two points are (1, 1) and (1, -4)
(-4-1)/(1-1)
=-5/0
= undefined (fractions with 0 base is undefined)