Answer:
-2/5
Explanation:
It can be easier to see the slope of a line if you draw it on a coordinate grid.
The slope is the "rise" divided by the "run", that is, the change in y divided by the change in x:
... slope = ∆y/∆x . . . . . . . . . where the symbol ∆ means "the change in"
Between your two points, the change in y (vertical distance) is -4 units; the change in x (horizontal distance) is 10 units. Then the slope is ...
... slope = -4/10 = -2/5
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The slope of a line is the same everywhere, so you can pick the closest pair of points on the line that have integer coordinates when you want to compute and express the slope as a fraction. (Of course, the slope is defined as ∆y/∆x whether these values are integers or not.)