document.write( "Question 822434: If the 4th term of an arithmetic sequence is 31 and the 8th term of the sequence is 59, find the 1st term of the sequence. \n" ); document.write( "
Algebra.Com's Answer #494985 by ewatrrr(24785)\"\" \"About 
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document.write( "Hi,
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document.write( "If the 4th term of an arithmetic sequence is 31 and the 8th term of the sequence is 59, find the 1st term of the sequence. 
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document.write( "\"a%5Bn%5D+=+a%5B1%5D+%2B%28n-1%29d\"
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document.write( "\"a%5B4%5D+=+a%5B1%5D+%2B3d+=+31\"
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document.write( "\"a%5B8%5D+=+a%5B1%5D+%2B7d+=+59\"
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document.write( " a1 + 7d = 59 
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document.write( " a1 + 3d = 31    |subtracting 2nd EQ from 1st
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document.write( "     4d = 28
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document.write( "      d = 7    and \"a%5B1%5D+=+highlight_green%2810%29\"    (a1 = 59-49)
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document.write( " CHECKING our answer***
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document.write( "\"a%5B4%5D+=+10+%2B+21+=+31\" \n" );
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