Hey there! Hello!
So, for this problem, there's one answer we can immediately figure out:
[tex]12-3=9[/tex]
You can also make use of "counters," as shown in my first attachment. The large group has 9, while the small group has three. It represents a separation between the two amounts.
You can also make use of a number line. To subtract, start at 12, then go towards zero (or to the left) three times. This will give you your number.
Hope this helped! Feel free to ask me any additional questions if you have any. :-)
