Step-by-step explanation:

Isn’t there supposed to be a picture?
Associative property is only applied to addition and multiplication. Thus, it can't be applied to subtraction. This property is manifested when you get the same answer no matter where you put the parenthesis. Example of associative property is:
(50 + 2) + (92 + 6) = 52+98 = 150
50 + (2+92) + 6 = 50 + 94 + 6 = 150
Here is the counter example for the subtraction of decimals:
(3.45 - 8.92) - (1.9 - 7.3) = -5.47 - ⁻5.4 = -0.07
3.45 - (8.92 - 1.9) - 7.3 = 3.45 - 7.02 - 1.9 = -5.47
As you can see, the answers are not the same.
Answer:
5x+4y=49.50, where:
x is the price per sub
y is the price per drink
Step-by-step explanation:
From the information provided, you can say that the result of adding up the price per sub for the quantity plus the price per drink for the quantity is equal to 49.50 that is the total amount spent, which can be expressed as:
5x+4y=49.50, where:
x is the price per sub
y is the price per drink