Final answer:
The formula for the nth term of the sequence is 12 - 3(n-1).
Step-by-step explanation:
The formula for the nth term of the sequence is
The value of n starts with 1 since the first term is 12.
To find the formula, we notice that each term in the sequence is 3 less than the previous term.
So, to find the nth term, we start with 12, and subtract 3 times the number of terms before it (n-1).