SOLUTION: A rental car agency charges $19 per day plus 10 cents per mile to rent a certain car. Another agency charges $21 per day plus 5 cents per mile to rent the same car. How many miles

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Question 1173091: A rental car agency charges $19 per day plus 10 cents per mile to rent a certain car. Another agency charges $21 per day plus 5 cents per mile to rent the same car. How many miles per day will have to be driven for the cost of a car from the first agency to equal the cost of a car from the second agency?

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
set the two equal to each other, since they are both functions of cost.
$19+0.10x=$21+.05x units are dollars and dollars/mile * mile
0.05x dollars/mile=$2
x=40 miles