Answer:
7 & -1
Step-by-step explanation:
Assuming you want the value of x...
Since the equation is wrapped in an absolute value, we must get x for both the positive and negative value.
Positive x
[tex]3x-9=12\\3x=21\\x=7[/tex]
Negative x
[tex]3x-9=-12\\3x=-3\\x=-1\\[/tex]
Both of these will equal 12 when tested.
[tex]|3(-1)-9|=12\\|-3-9|=12\\|-12|=12\\12=12\\[/tex]
[tex]|3(7)-9|=12\\|21-9|=12\\12=12\\[/tex]
