Answer:
Solution set = {-12, 12}
Step-by-step explanation:
Start by dividing both sides of the given equation by negative one, to get rid of the negative signs on both sides:

Now we consider the two possible cases:
1) The expression inside the absolute value symbol is a positive number, then :

and replacing it in the equation, this becomes:

which is our first answer.
2) The expression inside the absolute value symbol is a negative number, then :

and replacing it in the equation, this becomes:

which is our second possible answer.
Then the set of solutions is: {-12, 12}