Find an explicit formula for the arithmetic sequence

-45, - 30, - 15, 0, ...

an = - 45 + 15 (n - 1)

Step-by-step explanation:

The explicit formula for an arithmetic sequence is ...

an = a1 + d (n - 1)

where an is the n-th term; a1 is the first term (-45), and d is the common difference (15). Filling in the values for the given sequence, we find the formula to be ...

an = - 45 + 15 (n - 1)