SOLUTION: Given an arithmetic sequence, 2,−1,−4,−7,... Firstly, Find the common difference, then, find the 120thterm, and lastly, find which term is −595.

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Question 1170344: Given an arithmetic sequence, 2,−1,−4,−7,...
Firstly, Find the common difference, then, find the 120thterm, and lastly, find which term is −595.

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
common difference is -3
-595 is -597 from +2 or 199 terms after it or the 200th term
an=a1+(n−1)d
a200=2+(199)(-3)=-595
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a120=2+(119)(-3)=-355