SOLUTION: Is the sequence a[n]=6n-17 arithmetic? if it is what is its first term and its common difference

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Question 1126253: Is the sequence a[n]=6n-17 arithmetic?
if it is what is its first term
and its common difference
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

a%5Bn%5D=a%5B1%5D%2B%28n-1%29d....using nth term formula, we have
a%5Bn%5D=a%5B1%5D%2Bdn-d
a%5Bn%5D=dn%2B%28a%5B1%5D-d%29
since you are given
a%5Bn%5D=6n-17 , you see that
%28a%5B1%5D-d%29=-17+ and dn=6n
=>d=6, is common difference
and
a%5B1%5D-6=-17
a%5B1%5D=-17%2B6
a%5B1%5D=-11 is its first term