I know this is straightforward, and I have the line-by-line answer, but I can't understand how you get from:
(2x - 3y = 6) - 3y = - 2x + 6 (So here you have shifted the 2x over as you want ultimately just y on the left)
to y = 2x/3 - 2 (Where's the -3? Why is there a fraction on the right? What's happened to the +6?)
(Original post by tymbnuip)
Oh so you do it to the +6 AND the -2x. Got ya!
Yes you're "doing it" to the sides of the equation rather than the actual terms (at least that's one way of looking at it).
If you didn't, your equation would not hold. There's only a limited number of valid operations you can do to an equation (an equation states that something on the left side is equal to something on the right side) like add/subtract a number to each side or multiply the left expression and the right expression by the same factor (in your case that factor is -3)