Solve equations with variables on both sides.

Let's use "m" to represent miles and "C" to represent the total cost for one week.

Car Rental: $0.25 is a rate.. (dollars per mile) so it get's multiplied by miles to give dollars. We are going to just look at 1 week to not introduce any more variables. Thus the $240 per week is multiplied by 1 essentially just leaving the amount.

C = 240 + 0.25m

Minivan Rental: Again, $0.40 per mile is the rate to multiple by miles. Only looking at 1 week, so the $180 is a fee.

C = 180 + 0.40m

** Set the cost equations equal to each other and solve for miles.

240 + 0.25m = 180 + 0.40m

240 - 180 = 0.40m - 0.25m

60 = 0.15m

60/0.15 = m

400 miles in one week, the cost will be the same.

- Same thing for problem #7. Let's make "h" represent hours

Smith family

C = 289 + 16.50h

Jackson family

C = 274.60 + 18.75h

- Set equal and solve for hours.

289 + 16.50h = 274.60 + 18.75h

289 - 274.60 = 18.75h - 16.50h

14.40 = 2.25h

6.4 hours

yes

yes yes yes

answer: the first graph

step-by-step explanation: