Answer:
x = 325 miles
Step-by-step explanation:

Since x and y must be positive, 7x and 11y are positive either. That means 7x + 11y > 0. Then we would obtain N > 0 because 7x + 11y = N. That also means N must be positive. So if we set N to be zero or negative, there would be no solution. Thus, to produce an answer of No solution, the highest number N could be is 0.
Given the graph, you can assume that f(x) is the y of an equation.
When f(2) is given, this means that what is the y value when x=2?
As you can see, the solution is between 8 and 10. Meaning that the closest answer is 9.
Hope I helped :)
Four point two-hundred ninety three