No, because this changes the sign of x to negative instead of positive.
To tell this, we have to manipulate the first equation. Firstly, take the equation and give the right side a common denominator.
2x = (x - 12)/2 ----> Multiply by 2
4x = x - 12 ----> Subtract x
3x = -12
Since you see here that 3x = -12, whereas the comparative equation is positive 12, we know they are not equal.
