Answer:
3
Step-by-step explanation:
Let's go through this together.
Step 1) Rearrange Terms (Optional)
9 + x = 12
x + 9 =12
Step 2) Subtract 9 from both sides of the equation
x + 9 = 12
-9 -9
Step 3) Simplify
If we subtract 9 on both sides, we end up with:
x + 0 = 3
Since 0 no longer has any part in the equation, we can conclude that:
x = 3
