document.write( "Question 1044785: The first three terms of an arithmetic sequence are -12, -4, and 4. Which term is 212 ? \n" ); document.write( "

Algebra.Com's Answer #660182 by ikleyn(52794) $\"\"$ $\"About$

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\n" ); document.write( "The first three terms of an arithmetic sequence are -12, -4, and 4. Which term is 212 ?
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document.write( "212 = -12 + 8*(n-1).   (1)\r\n" );
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document.write( "You are asked to find n.\r\n" );
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document.write( "From (1) n-1 =  = 28.\r\n" );
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document.write( "Hence, n = 28 + 1 = 29.\r\n" );
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document.write( "Check.  -12 + 8*(29-1) = -12 + 8*28 = 212.  Correct !\r\n" );
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document.write( "Answer.  212 is the 29-th term.\r\n" );
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