Aaron has a budget of $100 per month to spend on lunch. He made a table showing the total amount of lunch money he will have left after the given number of lunches.


Number of lunches 0 5 10 15

Total amount of lunch money left ($) 100 75 50 25

Which equation, in standard form, represents the relationship between the number of lunches, x, and the amount of lunch money Aaron will have left, y?


x + 5y = 100


100x + y = 5


x + 100y = 5


5x + y = 100