document.write( "Question 368097: what is the sum of the first 4 terms of the arithemetic sequence in which the 6th term is 8 and the 10th term is 13 \n" ); document.write( "
Algebra.Com's Answer #262315 by stanbon(75887)\"\" \"About 
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what is the sum of the first 4 terms of the arithemetic sequence in which the 6th term is 8 and the 10th term is 13
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\n" ); document.write( "a(6) = a(1) + 5d = 8
\n" ); document.write( "a(10)= a(1) +12d = 13
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\n" ); document.write( "Subtract the 1st line from the bottom:
\n" ); document.write( "7d = 5
\n" ); document.write( "d = 5/7
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\n" ); document.write( "Substitute for d and solve for a(1):
\n" ); document.write( "a(1) + 5(5/7) = 8
\n" ); document.write( "a(1) = 8-25/7
\n" ); document.write( "a(1) = 31/7
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\n" ); document.write( "Sum of the 1st 4 terms = ?
\n" ); document.write( "a(4) = (31/7) + 3(5/7) = 46/7
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\n" ); document.write( "S(4) = (4/2)(1st + 4th)
\n" ); document.write( "S(4) = 2((31/7)+(46/7)) = 2(77/7) = 22
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.\r
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