Question

An arithmetic sequence is given below.

16, 13, 10, 7, ...
Which is the explicit formula for the nth term an?

Answer 1

Nth term: -3n+19

Explanation:

You can see the sequence is decreasing by 3 each time so the Nth term is -3n.

The 0 term would therefore be 19 so the formula would be -3n+19.

Answer 2

The answer is

a (n) = -3n +22