Answer:
x = 3.6
Step-by-step explanation:
3/5 = x/6
multiply both sides by 6
18/5 = x
as a decimal
x = 3.6
So, to figure out this problem you first need to solve for how much you have left after paying the base fee. Take the total ($84) and subtract by the base fee ($27). You will get 57 as your answer. Then, take $57 and divide it by $0.15 to get your answer. It is 380 minutes each month. The equation here is 84=27+0.15x.
It's asking for a composition function where you insert the function g(x) into f(x).
f(g(x))=10(x+8)+25
f(g(x))=10x+80+25
f(g(x))=10x+105