Answer:
Exponential Function
Step-by-step explanation:
If you graph the numbers you'll get an exponential function graph. Hope this helps!
$ 9.5
total money is $20
on lunch = 1/8 × 20 = 5/2 = $2.5
on movies = 2/5 × 20 = $8
total spent = 2.5+8 =$ 10.5
left money = 20-10.5 = $ 9.5
and minimum value of f(x) is 12