Write an explicit formula for a (n), the n^th term of the sequence 180,-30,5

a (n) = 180· (1/6) ^ (n-1)

Step-by-step explanation:

The generic formula for a geometric sequence is ...

a (n) = a (1) ·r^ (n-1)

Your sequence has a first term of a (1) = 180 and a common ratio of r=-1/6, so the explicit formula is ...

a (n) = 180· (1/6) ^ (n-1)