3√12 - 6√1 - 4√9 / 3 = 3√3 - 6√1, right

Thanks for assisting.

CORRECT

Depends on where the parentheses belong.
(3√12 - 6√1 - 4√9)/3 = (6√3 - 6 - 12)/3
= (6√3 - 18)/3
= 2√3 - 6

wrong
3√12 - 6√1 - 4√9 / 3
= 6√3 -10