Notice that there is a base fee of $14.95 for the rental.
They also give you a charge for miles driven ($0.90).
We know that Dale paid $158.05 when he returned the truck. We need to find the number of miles driven (x)
Let's first write an equation that combines the fixed rate of $14.95 with the amount coming from the number of miles driven:
Number of miles times the amount they charge per mile is the extra to be added to the fixed rate.
Notice as well, that instead of typing 90 cents, I typed $0.90 (in dollars) for the price they charge per mile. That is to have all the money units equal in order to perform the addition of quantities at the end.
Now, going back to the amount charge for "x" miles driven, we have:
amount for miles driven = 0.90 x (the product of 0.90 and x)
Then our equation for total charges becomes:
Total = 14.95 + 0.90 x
In our case we know the total that was paid, so we replace it in the equation:
158.05 = 14.95 + 0.90 x
and we solve for x:
158.05 - 14.95 = 0.90 x
143.1 = 0.90 x
x = 143.1/0.90
x = 159
Therefore, Dale drove 159 miles.