An arithmetic sequence (a_n) is as follows:
where 
is the first term and d is the constant difference,
thus, we see that the n'th term of an arithmetic sequence is
in our particular case d=5, the third term is 8, so we have:
and the general term is
,
Answer: first term is -2, n'th term is -2+5(n-1)
thus, we see that the n'th term of an arithmetic sequence is
in our particular case d=5, the third term is 8, so we have:
and the general term is
Answer: first term is -2, n'th term is -2+5(n-1)