Answer:
The customer bought 5 hamburgers with cheese and 1 hamburger without cheese.
Explanation:
Make the expression 18x + 12y = 104 and remember, there are 6 total hamburgers. Break down the equation one by one.
6 hamburgers (all with cheese):
18 x 6 = 108, which is over 104 (the total).
6 hamburgers (5 with cheese and 1 without):
18 x 5 = 90
12 x 1 = 12
90 + 12 = 102, which is the closest number that's less than 104 (the actual price).