Lets work out the problem from the beginning. Let

be the number of hours worked. We know that you paid $65 for each hour, and remember that the numbers of hours worked is

, so you paid for those hours

. We also know that you paid $132 for parts, a total cost of $229.5, so:
parts + worked hours = total cost

And now that we have our equation from the model, lets solve for

to find how many hours took to the repair the car:




We can conclude that it took 1 and a half hour to repair the car.