SOLUTION: Express the general term a(n), (with n as a subscript), for an arithmetic sequence whose 7th term is 11 and 20th term is -41. Then find the 9th term.
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-> SOLUTION: Express the general term a(n), (with n as a subscript), for an arithmetic sequence whose 7th term is 11 and 20th term is -41. Then find the 9th term.
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Question 888309: Express the general term a(n), (with n as a subscript), for an arithmetic sequence whose 7th term is 11 and 20th term is -41. Then find the 9th term. Answer by josgarithmetic(39617) (Show Source):
You can put this solution on YOUR website! General term of arithmetic sequence is a+(n-1)d using n as the index and d as the common difference.
The initial term is a.
n=7, term is 11;
n=20, term is -41.
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Start with Elimination Method to first find d.
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Using the n=7 equation,
General term is .
You can find whichever term you want.