The answer is L = 59 + 2(d). If we plug in our numbers, we will get L = 59 + 2(32). 2*32 is 64, and if you add 59 you get 123 miles.
This isn’t apart of the question, but 59 would be the y-intercept. 2 miles per day (2/1) is the slope.
By the chain rule,
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We also have
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,
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, and
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, so at this point we get
The answer is c. bc it doesn't need to be tested