I’m starting to understand the distributive argument you and others are presenting better, but I still have a problem not seeing 48/2 as the multiplier outside the parenthesis.
That would make the expression 24(9+3) = 24(12) = 288.
In order to evaluate the 2(9+3) before the 48/2, one would have to ignore the order of operations in the overall equation. I can’t find anything that tells me to ignore the left-to-right precedence outside the parenthesis.
First you need to understand that 48 divided by 2 x (9+3) is not the same as 48 divided by 2(9+3).
2(12) is a number and that number is 24.
The problem is 48 divided by 2(12) and not 48 divided by 2 times 12.
The distributive property eliminates any confusion as to what should be calculated first:
An easy way is to think of 2(9+3) as (2(9+3)). By convention, it has been agreed that 2(9+3) is to be treated as (2(9+3)).
If the distributive property did not exist, 288 would be the correct answer, but it does exist, so the correct answer must be 2.
As for having a problem not seeing 48/2 as a valid multiplier, you just need to accept that the rules are the rules and having such rules make mathematical life simpler and less confusing. In your case, if you did not know the rule, I can see why you thought the answer was 288.
Now that you have additional information, I hope that you can now understand why the answer must be 2.