Answer:
undefined
Explanation:
Slope is a measure of the vertical change relative to the horizontal change. On an x-y graph, it will be the difference in y-coordinates divided by the corresponding difference in x-coordinates. It is often referred to using the letter m.
m = (y2 -y1)/(x2 -x1) . . . . . slope of line between points (x1, y1) and (x2, y2)
It does not matter which points you call point 1 and point 2.
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For the points given on the graph we can compute the slope to be ...
m = (2 -(-3))/(-1 -(-1)) = 5/0
The zero in the denominator makes this value "undefined." So, we say the slope of any vertical line is "undefined."