Final answer:
The recursive rule for the sequence -3, 6, 15, 24, ... is an = an-1 + 9.
Step-by-step explanation:
The recursive rule for the sequence -3, 6, 15, 24, ... is an = an-1 + 9 (option a).
This means that each term in the sequence is obtained by adding 9 to the previous term.
For example, starting with the first term -3, we can apply the recursive rule to find the second term: -3 + 9 = 6. Continuing this pattern, we can find the rest of the terms in the sequence.