Using a linear function, the costs are given as follows:
A linear function is modeled by:
y = mx + b
In which:
For this problem, we have that:
Hence the cost for r rides is given by the following linear function:
C(r) = 15 + 4r.
The cost for 7 rides is given by:
C(7) = 15 + 4(7) = 15 + 28 = $43.
More can be learned about linear functions at https://brainly.com/question/24808124
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