SOLUTION: find a[20] when a[1]=9 and d=2

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Question 635192: find a[20] when a[1]=9 and d=2
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

find a[20] when a[1]=9 and d=2 

Arithmetic Sequence

+a%5Bn%5D+=+a%5B1%5D+%2B+%28n-1%29d

a%5B20%5D+=+9+%2B+19%2A2+=+47