2 + 16 = 6w - 2 + 2
18 = 6w
So, now we have 18 = 6w. We're getting close, but we're not there yet. See, the w isn't by itself yet. It's still 6w (or 6*w). Now, we need to continue cancelling out whatever is happening to the w that's keeping it from being by itself. Since we have 6w, 6 times w, ask yourself what is the opposite of multiplying by 6? Dividing by 6! If you take 6w and divide it by 6, the multiply by 6 is cancelled out by the divide by 6, (6*w / 6 = w). Just like before, we can't do it to only one side, we have to do it to both.
18 / 6 = 6w / 6
3 = w
So, now we know that w equals 6.
I may have covered things you knew, but I wanted to make sure and hit all the points. Good luck!