1/3 divided by 1/6 = 2
2 miles per day
Your points: (5,2)
Your inequality: x - y < 0
Plug 5 in for x and y in for 2
5 - 2 < 0.
Simplify the left side
3 < 0.
3 is not less than 0
(5,2) is not a solution of x - y < 0
any combination would work out. the most common is x and y. or you may use f(x) and x.

Hope you could understand.
If you have any query, feel free to ask.
One solution.
They have different slopes and therefore must have one solution.