First you would want to add all like terms. So add -2x and -x which will give you the equation -3x+8=?. Now you want to get 8 on the other side to simplify the equation even more so subtract 8 on both sides. -3x=-8. Finally you want to isolate x by dividing by -3 on both sides which will leave you with x=8/3 or x=2 2/3
