document.write( "Question 928433: How many terms of the arithmetic sequence -12,-3,6... Must be added to arrive at a sum of 363? \n" ); document.write( "

Algebra.Com's Answer #563986 by Fombitz(32388) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"a%5Bn%5D=-21%2B9n\"$
\n" ); document.write( " $\"S%5Bn%5D=%28n%2F2%29%28a%5B1%5D%2Ba%5Bn%5D%29\"$
\n" ); document.write( " $\"363=%28n%2F2%29%28-12-21%2B9n%29\"$
\n" ); document.write( " $\"726=n%289n-33%29\"$
\n" ); document.write( " $\"9n%5E2-33n=726\"$
\n" ); document.write( " $\"3n%5E2-11n-242=0\"$
\n" ); document.write( " $\"%28n-11%29%283n%2B22%29=0\"$
\n" ); document.write( "Only the positive solution makes sense here.
\n" ); document.write( " $\"n-11=0\"$
\n" ); document.write( " $\"n=11\"$ $\"terms\"$ \n" ); document.write( "

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