The goal here is to get X alone on one side of the equation.
Whatever you do to one side you must also do to the other side
Subtract 6x from both sides
6x+4=8x-2
-6x -6x
Add 2 to both sides
4=2x-2
+2 +2
Divide both sides by 2
6=2x
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2 2
6/2=x
3=x