first off you multiply -2 two by everything in parentheses then you do the same on the other side except not the -2. than you get -4x-6=-4x-4-2
than add all like terms to get -4x-6=-4x-6than bring the -six over and add it to the other six to get -4x=-4x-0. after that you bring the -4x over and add it to the other side and you get x=0.