document.write( "Question 257426: The first three terms of an arithmetic sequence, in order, are 2x + 4, 5x – 4, and
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Algebra.Com's Answer #189340 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
The first three terms of an arithmetic sequence, in order, are 2x + 4, 5x – 4, and
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document.write( "If it's an arithmetic sequence then\r\n" );
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document.write( "the second term minus the first term must be equal to third term minus the second term.\r\n" );
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document.write( "So \r\n" );
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document.write( "(5x-4) - (2x+4) = (3x+4) - (5x-4)\r\n" );
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document.write( "5x - 4 - 2x - 4 = 3x + 4 - 5x + 4\r\n" );
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document.write( "         3x - 8 = -2x + 8\r\n" );
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document.write( "        3x + 2x = 8 + 8\r\n" );
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document.write( "             5x = 16\r\n" );
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document.write( "              x = \"16%2F5\"\r\n" );
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document.write( "     \r\n" );
document.write( "2x + 4, 5x – 4, and 3x + 4\r\n" );
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document.write( "Substitute \"16%2F5\" for x in all three terms:\r\n" );
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document.write( "\"2x+%2B+4\" \r\n" );
document.write( "\"2%2816%2F5%29%2B4%29\"\r\n" );
document.write( "\"32%2F5%2B20%2F5\" \r\n" );
document.write( "\"52%2F5\"\r\n" );
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document.write( "\"5x+%96+4\"\r\n" );
document.write( "\"5%2816%2F5%29-4\"\r\n" );
document.write( "\"16-4\"\r\n" );
document.write( "\"12\"\r\n" );
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document.write( "\"3x+%2B+4\"\r\n" );
document.write( "\"3%2816%2F5%29+%2B+4\"\r\n" );
document.write( "\"48%2F5%2B4\"\r\n" );
document.write( "\"48%2F5%2B20%2F5\"\r\n" );
document.write( "\"68%2F5\"\r\n" );
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document.write( "So the common difference d is \r\n" );
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document.write( "\"12+-+52%2F5\"\r\n" );
document.write( "\"60%2F5-52%2F5\"\r\n" );
document.write( "\"8%2F5\"\r\n" );
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document.write( "the sum of the first n terms is given by the formula\r\n" );
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document.write( " and \"d=8%2F5\" and \"a%5B1%5D=52%2F5\"\r\n" );
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document.write( "\"+S%5B10%5D=%2810%2F2%29%282%2852%2F5%29%2B%28%2810%29-1%29%288%2F5%29%29\"\r\n" );
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document.write( "\"S%5B10%5D=%285%29%28104%2F5%2B%289%29%288%2F5%29%29\"\r\n" );
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document.write( "\"S%5B10%5D=%285%29%28104%2F5%2B72%2F5%29%29\"\r\n" );
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document.write( "\"S%5B10%5D=%285%29%28176%2F5%29%29\"\r\n" );
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document.write( "\"S%5B10%5D=176\"\r\n" );
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document.write( "Edwin
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