In order to solve for a nth term in an arithmetic sequence, we use the formula written as:
an = a1 + (n-1)d
where an is the nth term, a1 is the first value in the sequence, n is the term position and d is the common difference.
a8 = 45 + (8-1)-6
a8 = 45 + (7)(-6)
a8 = 3