y = total cost
x = the number of miles traveled
Rent a Truck: y = 0.20x + 40
[they rent a moving truck for $40(upfront charge) plus $0.20 per mile(x)]
Moving R Us: y = 1x or y = x
[they rent a moving truck for only $1.00 per mile(x) with not upfront charge]
To find when the cost will be the same, set the equations equal to each other:
[Rent a Truck = Moving R Us]
0.20x + 40 = x Subtract 0.20x on both sides
40 = 0.80x Divide 0.80 on both sides
50 = x x = 50 miles
[proof]
Rent a Truck:
y = 0.20x + 40 Plug in 50 for x
y = 0.20(50) + 40
y = 10 + 40
y = 50 $50
Moving R Us
y = x Plug in 50 for x
y = 50 $50