Using it's concept, it is found that the slope of the function is of -4.
The slope of a function is given by the change in the output of the function divided by the change in the input.
For this problem, in 9 months, his weight changed from 265 pounds to 229 pounds, hence it changed -36 pounds, which means that the slope is of:
m = -36/9 = -4.
More can be learned about the slope of a function at https://brainly.com/question/24808124
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