Given:
There are given that the truck rental is $20 plus $0.40mi/hr.
Step-by-step explanation:
According to the question:
We need to find the number of miles if his bill was $58.
So,

Then,
Subtract 20 from both sides of the above equation.
So,

Now,
Divide by 0.40 on the above equation:
So,

Final answer:
Hence, Ken traveled 95 miles.