The question is find the equation, in the function and standard notations, that represent the amount spent in the range of 0 to 5 rides.
Constant cost: $30
Independent variable, number of rides: r
Variable cost: $2r
Total spend, s(r): 30 + 2r
Function: s(r) = 30 + 2r, for 0 ≤r ≤ 5 ----- this is the function notation
Standard form: s(r) is the dependent variable = s
s = 30 + 2r => s - 2r = 30 =>
s + (-2)r = 30, for 0 ≤ r ≤ 5 ------ this is the standard form