The given equation is,

It can be rewritten in the form of y=mx+c, where c is the y intercept.
Hence,

Put different values for x and find value of y.
When x=0, y=1.
When x=1,

The graph is,
Hmm. Try counting the side of the shape and add the sides. Using the sides as numbers you may be able to solve the problem.
You would have about 3472 Hours
.18\8=1.44 for 8 hour
5000/1.44=3472
Hope this helps :)