So we know that its $42 a day for Truck A, and its another $0.72 per mile, so we can use d for the number of days, and m for the number of miles:
Truck A: 42d+0.72m
We also know that Truck Company B charges $70 per day and an additional $0.12 a mile. Again, we can use d for the number of days and m for the number of miles:
Truck B: 70d+0.12m
Now if we start plugging in values, we will find when they cost the same. The rest is in the picture. Your answer is m≈47
