Using linear functions, the cost will be the same, of $70, when there are 5 students.
A linear function is modeled by:
y = mx + b
In which:
In this problem, the functions are:
The costs are the same when:
45 + 5x = 35 + 7x
2x = 10
x = 5.
The cost is:
y = 45 + 5 x 5 = $70.
More can be learned about linear functions at https://brainly.com/question/24808124
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