The line has a "rise" between the two points of -4 units for a "run" of +1 unit. The slope is the ratio ...
m = rise/run = -4/1 = -4.
The slope is -4.
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<em>Additional comment</em>
A "whole number" must be non-negative. Here, the slope is negative. If you're restricted to "a fraction or a whole number", then the appropriate answer is the fraction -4/1. We suspect that "integer" is meant where "whole number" is used.
