Answer: X=+3
Explanation:
1) Move all terms to the left:
X-3-(5X-12-X)=0
2) We add all the numbers together, and all the variables
X-(4X-12)-3=0
3) Get rid of parentheses
X-4X+12-3=0
4) Add all the numbers together, and all the variables
-3X+9=0
5) Move all terms containing X to the left, all other terms to the right
-3X=-9
X=-9/-3
X=+3