Hello there! :)
Answer:

*THE ANSWER MUST HAVE A NEGATIVE SIGN!*
Explanation:
First, you subtract by 12 from both sides of an equation.

Subtract by numbers from left/right.


Divide by 4 from both sides of an equation.

Divide by the numbers from left/right.

, is the final answer.
Hope this helps!
Thanks!
Have a nice day! :)
:D
-Charlie