A truck can be rented from Company A for ​$ 80a day plus ​$ 0.20per mile.Company B charges ​$50 a day plus ​$ 0.50 per mile to rent the same truck.

Answer 1

for A: Cost = 80D + .2M

for B Cost =50D +.5M

Set the costs equal to get when it doesn't matter which you rent

80D +.2M =50D +.5M

subtract 50D +.2M from both sides

30D = .3M

divide by 3

10D = .1M

multiply by 10

100D = M

or D= 0.01M

If you plan on driving an average 100 miles per day, it doesn't matter which you use A or B

If you plan on driving more than 100 miles per day, use Company A

If you plan on driving less than 100 miles per day, use Company B

1 day at 100 miles costs $50 + $50 in mileage for total $100 for Company B

1 day at 100 miles costs $80 + $20 in mileage for total $100 for Company A

2 days at 200 miles costs $100+$100 = $200 total with Company B

2 days at 200 miles costs $160 + $40 = $200 total with Company A