document.write( "Question 1119562: Hi, could you help me with this question here please?\r
\n" ); document.write( "\n" ); document.write( "\"Write the explicit rule for this arithmetic sequence. The 4th term = 5, and the 10th term = 23\"\r
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Algebra.Com's Answer #735120 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
the formula for an arithmetic sequence is:\r
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\n" ); document.write( "\n" ); document.write( "An = A1 + (n-1) * d\r
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\n" ); document.write( "\n" ); document.write( "your 4th term is equal to 5 and your 10th term is equal to 23.\r
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\n" ); document.write( "\n" ); document.write( "using the formula, you get:\r
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\n" ); document.write( "\n" ); document.write( "A4 = A1 + (4-1) * d\r
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\n" ); document.write( "\n" ); document.write( "A10 = A1 + (9-1) * d\r
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\n" ); document.write( "\n" ); document.write( "these simplify to:\r
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\n" ); document.write( "\n" ); document.write( "A4 = A1 + 3d
\n" ); document.write( "A10 = A1 + 9d\r
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\n" ); document.write( "\n" ); document.write( "you are given that A4 = 5 and A10 = 23.\r
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\n" ); document.write( "\n" ); document.write( "the formulas become:\r
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\n" ); document.write( "\n" ); document.write( "5 = A1 + 3d
\n" ); document.write( "23 = A1 + 9d\r
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\n" ); document.write( "\n" ); document.write( "subtract the first formula from the second to get:\r
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\n" ); document.write( "\n" ); document.write( "18 = 6d\r
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\n" ); document.write( "\n" ); document.write( "solve for d to get d = 3.\r
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\n" ); document.write( "\n" ); document.write( "in both equations, replace d with 3 to get:\r
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\n" ); document.write( "\n" ); document.write( "5 = A1 + 3 * 3
\n" ); document.write( "23 = A1 + 9 * 3\r
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\n" ); document.write( "\n" ); document.write( "these simplify to:\r
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\n" ); document.write( "\n" ); document.write( "5 = A1 + 9
\n" ); document.write( "23 = A1 + 27\r
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\n" ); document.write( "\n" ); document.write( "solve for A1 in both equations to get:\r
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\n" ); document.write( "\n" ); document.write( "A1 = -4 in the first equation.
\n" ); document.write( "A1 = -4 in the second equation.\r
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\n" ); document.write( "\n" ); document.write( "that's good, since A1 needed to be the same in both equations.\r
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\n" ); document.write( "\n" ); document.write( "since A1 = -4 and d = 3, your sequence is as follows:\r
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document.write( "term number      term value\r\n" );
document.write( "1                  -4\r\n" );
document.write( "2                  -1\r\n" );
document.write( "3                   2\r\n" );
document.write( "4                   5 ***** 4th term in sequence.\r\n" );
document.write( "5                   8\r\n" );
document.write( "6                  11\r\n" );
document.write( "7                  14\r\n" );
document.write( "8                  17 \r\n" );
document.write( "9                  20\r\n" );
document.write( "10                 23 ***** 10th term in sequence.\r\n" );
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\n" ); document.write( "\n" ); document.write( "here's a reference on arithmetic sequences.\r
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\n" ); document.write( "\n" ); document.write( "https://www.mathsisfun.com/algebra/sequences-sums-arithmetic.html\r
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