I won't do this for you, but I can give you a hint. Replace your f variable with -2, -1, 0, 1, and 2. Then take said f variable and put it in your y boxes. Then just get a calculator and do the work on there. It should be pretty easy.
It would help to first find the unit rate. We know that the plane flies 810 km per 1.5 hours. Divide by 1.5 on both sides:
810/1.5 = 540 km/hour
Then, multiply both the hour and the distance by 2:
540 * 2 = 1080 km/2 hours.
Answer:
Each coupon was worth $8.
Hope this is helpful! =)
