SOLUTION: Find the first term and the common difference of the arithmetic sequence whose 5th term is 7 and 13th term is 39. Can you please help?
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Question 853876: Find the first term and the common difference of the arithmetic sequence whose 5th term is 7 and 13th term is 39. Can you please help? Found 2 solutions by richwmiller, Vladdroid:Answer by richwmiller(17219) (Show Source):
You can put this solution on YOUR website! an = a + (n - 1)d
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39 = a + 12d
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7 = a + 4d
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32=8d
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d=4
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a=-9
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