Question 1196226
Let X = number of miles the truck must be driven in a day

The equation
80 + 0.6X = 50 + 0.9X

Combine like terms
80 - 50 = 0.9X - 0.6X
30 = 0.3X
X = 30/0.3

X = 100 miles

Answer:
The truck must be driven at least 100 miles in a day to make the rental cost for Company A a better deal than company​ B's.