Follow the meaning of the "=" sign. That is the left side of the equation is equal to the right side of the equation.
so, if one does something to one side of the equation, the exact same thing must be done on the other side.
3y - 6 = 9 - 2x.
Add 6 to both sides and reduce if possible.
3y - 6 +6 = 9 -2x +6 -> 3x +(-6 +6) = 9 +6 -2x
since -6+6 = 0, the right side of the equation becomes;
3x +(-6+6) = 3x.
And the left side becomes;
9+6 -2x = 15-2x
this leave the original equation as;
3y = 15 - 2x
Now divide both sides of the equation by 3;
3y/3 = (15 -2x)/3
left side becomes:
3y/3 = y.
And the right side becomes
(15 - 2x)/3 = 15/3 - 2x/3 = 5 - (2/3)*x
The final form becomes:
y = 5 - (2/3)*x
Done.
just remember the meaning of the equal sign: keep both sides of the equation equal and things will work out.
+10 
