document.write( "Question 964478: For the arithmetic sequence, find a12 and an, when a1=3 and a4=-12 \n" ); document.write( "

Algebra.Com's Answer #589550 by Fombitz(32388) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"a%5Bn%5D=a%5B1%5D%2B%28n-1%29%2Ad\"$
\n" ); document.write( " $\"a%5B4%5D=a%5B1%5D%2B%284-1%29d\"$
\n" ); document.write( " $\"-12=3%2B3d\"$
\n" ); document.write( " $\"3d=-15\"$
\n" ); document.write( " $\"d=-5\"$
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( " $\"a%5B12%5D=a%5B1%5D%2B%2812-1%29%2A%28-5%29\"$
\n" ); document.write( " $\"a%5B12%5D=3-55\"$
\n" ); document.write( " $\"a%5B12%5D=-52\"$
\n" ); document.write( " \n" ); document.write( "

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