You're going to want to take the total, which is $353.00 and subtract the initial cost, which is $84.00, the number now should be $269. Using that total divide it by $68.00, there you should find your answer of about 4 hours. The precise answer is 3.99588235. But you would round that to 4 hours.
First you cancel 7 and 28, and 3 and 9, so that leaves you with 4/3 x 15/17, then you cancel 3 and 15 so you get 4x5/17 which should give you 20/17!
Answer:
Draw a vertical line passing through (-3,0)
