Answer:
21 and/or -21
Explanation:
Add 12 to both sides to get |2x| = 42
Divide both sides by 2 to get |x| = 21
Since it is absolute value it means the answer could be either 21 or -21 since both would fit into the equation in place of x. The formal symbol is 21 with a plus sign over a minus sign, which my keyboard doesn’t have. Hope that helps!