This was never a programming question, it was always an algebra problem.
Says who?
If it was algebra, it wouldn't have used a "division sign." (come to think of it, not many programming languages have that either.)
Both of these are fine:
48
------- (9+3)
2
and
48
---------
2(9+3)
You treat 2(9+3) as a "term".
Wikipedia says
In elementary mathematics, a term is either a single number or variable, or the product of several numbers or variables separated from another term by a + or - sign in an overall expression.
and this doesn't fit. Why is that any more a term than (48/2)(9+3) ? It's not a polynomial with multiplicative terms added together...
(although I'm inclined to agree that there would be less argument about 48÷2X
If it were algebra, you might automatically assume that simple constants were already simplified.)