document.write( "Question 859194: Find 'n' for an arithmetic sequence for which Sn= 345, a=12, and d=5.\r
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Algebra.Com's Answer #517612 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
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document.write( "Hi,
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document.write( "          n(19 + 5n) = 690
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document.write( "          5n^2 + 19n - 690 = 0
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document.write( " Tossing out negative solution
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document.write( "      n = 10\r
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