................. ..............
5(x+3), the binomial has a common multiple of 5, so we factor it out.
Let x = # of monthly fee
f(x) = (50x + 30)/x
average cost will be below 56 for how many months?
(50x + 30)/x = 56
50x + 30 = 56x
56x - 50x = 30
6x = 30
x = 5
answer:
the average cost will be below $56 for 5 months