document.write( "Question 481803: Find the sum of the series described by a1=-18,d=3 and n=20 \n" ); document.write( "
Algebra.Com's Answer #329869 by ewatrrr(24785)\"\" \"About 
You can put this solution on YOUR website!
 
\n" ); document.write( "Hi,
\n" ); document.write( "a1=-18,d=3 and n=20
\n" ); document.write( "\"S%5Bn%5D+=%28n%2F2%29%282a%5B1%5D+%2B+%28n-1%29d%29\"
\n" ); document.write( "\"S%5B20%5D+=%2820%2F2%29%282%2A-18+%2B+%2819%293%29=+-90\" \n" ); document.write( "
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