Simple...
you have: -x=2-3x+6
You must isolate the variable x as this is what you are trying to find-->>>
-x=2-3x+6
-x=-3x+8
-x=-3x+8
+3x +3x
2x=8
x=4
To make sure you are correct-->>plug it in
-(4)=2-3(4)+6
-4=2-12+6
-4=-10+6
-4=-4
Thus, your answer.