So 70 miles per hour is 70 mile/1hour
1 mile=5280 feet
70 tmes 5280=feet=36,960
so 36,960 feet per hour
I don’t know if you meant 7 hours or 7 1/2 hours, but if it was in 7 hours, the answer would be around 15 square feet. If it was 7 1/2 hours, it would be 14 square feet.
Take x =4, then you have y = -1 ; (4,-1)
For x = -1, then y = 2; (-1,2)
This two points are in the function
But, in your graph, these points are not found. Then, it's wrong.