SOLUTION: a1=20,r=-3,n=6 find an

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Question 974658: a1=20,r=-3,n=6
find an
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
Memorize the formula

a%5Bn%5D%22%22=%22%22a%5B1%5Dr%5E%28n-1%29

Plug in and simplify: 

a%5B6%5D%22%22=%22%2220%28-3%29%5E%286-1%29

a%5B6%5D%22%22=%22%2220%28-3%29%5E5

a%5B6%5D%22%22=%22%2220%28-243%29

a%5B6%5D%22%22=%22%22-4860

Edwin