Respuesta :

Answer:

               400 miles  

Step-by-step explanation:

x    -  miles driven

140 + 0.70x    -  a day cost of renting from A

60 + 0.90x    - a day cost of renting from B

140 + 0.7x = 60 + 0.9x

   - 60           - 60

80 + 0.7x = 0.9x

    -0.7x       -0.7x

    80  =  0.2x

    ×5         ×5

 400  =  x