Answer:
x = 8
Explanation:
Given the initial fee of $5.00, and the additional cost of $2.50 for every mile the taxi drives:
We can establish the following cost function:
C(x) = 2.50x + 5.00
Where:
C(x) = total cost of taxi fare (same as the variable, "y" in linear equation)
x = number of miles driven
$5.00 = initial or flat fee (same as the y-intercept, "b," in linear equation).
We can find out the number of x miles the taxi drove for the $25.00 total cost that Justin paid for the fare:
C(x) = 2.50x + 5.00
$25 = 2.50x + 5.00
Subtract 5.00 from both sides of the equation:
$25 - 5.00 = 2.50x + 5.00 - 5.00
$20 = 2.50x
Divide both sides by 2.50 to solve for x:

8 = x
Justin spent $25 for a taxi ride that travelled for 8 miles.