-6x is the correct answer
Answer:
The first term is:
Step-by-step explanation:
The arithmetic sequence is defined by

where
is the first term
is the common difference
as
the 17th term of an arithmetic sequence is 51.
i.e. 
so

∵
,
, 
∵ 

Therefore, the first term is:
They are both in standard form.
Answer:
Step-by-step explanation:
i Believe its A. B. And D. But i could be wrong
Answer:
Step-by-step explanation:ffcrrer