Answer:
f = 6y + 3
Step-by-step explanation:
<u>The equation to reflect this condition is:</u>
<u>Where</u>
Check the picture below.
..............answer..
12
Remark
I can't use a symbol for the currency. I'll just get the answer in numbers. You can add the symbol.
Solution
First day: 50
Second day: - 20
Third day: - 18
50 - 20 - 18 = 12