document.write( "Question 859198: Find 'n' for an arithmetic sequence for which Sn=345, a=12, and d=5. \n" ); document.write( "

Algebra.Com's Answer #517613 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
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document.write( "Hi, Previously Posted
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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 \n" );
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