The best way to find out is to make sure each equations are in equal forms. In this case, I’d like to make sure that both equations are expanded.
Although 6x+12 is expanded, 2(3x–6) is not. All you have to do is multiply both numbers inside the parentheses with the number on the outside.
2(3x–6)
2×3x=6x; 2×(–6)=–12
So, 2(3x–6) is 6x–12.
However, that does mean that 6x–12≠6x+12. (The expressions are NOT equivalent.) This is because although the variable 6x are the same, 12 is not equal to –12, meaning they aren’t the same number.