Answer:
A. an = 5 + (n - 1)(-4)
Step-by-step explanation:
The explicit formula of an arithmetic sequence has the form
an = a1 + (n-1)d
Where a1 is the first term and d is a common difference.
Now, the recursive formula is
a1 = 5
an = a(n-1) - 4
So, we know that a1 = 4 and d = -4 because the common difference is the difference between two consecutive values.
Then, the explicit formula is
an = 5 + (n - 1)(-4)
So, the answer is A