Hi. You cannot do this I am afraid. If you want to divide by 3 you must divide all terms by 3 and you have not done the root6. The best way to avoid this mistake is only cancel if you can factorise out a common factor e.g. 3x + 12 over 3y you can simply because it is 3(x + 4) over 3(y). Here you can see the 3 will cancel leaving (x + 4) over (y).
