document.write( "Question 20121: Find all the integral values for k for which the trinomial can be factored?
\n" ); document.write( "z^2+kx+12
\n" ); document.write( "r^2+kr+20 \n" ); document.write( "
Algebra.Com's Answer #9703 by Earlsdon(6294)\"\" \"About 
You can put this solution on YOUR website!
Try this: For \"x%5E2+%2B+kx+%2B+12\"\r
\n" ); document.write( "\n" ); document.write( "What are the integral factors of +12?\r
\n" ); document.write( "\n" ); document.write( "\"%2B12+=+%281%29%2812%29\"
\n" ); document.write( "\"%2B12+=+%282%29%286%29\"
\n" ); document.write( "\"%2B12+=+%283%29%284%29\"
\n" ); document.write( "\"%2B12+=+%28-1%29%28-12%29\"
\n" ); document.write( "\"%2B12+=+%28-2%29%28-6%29\"
\n" ); document.write( "\"%2B12+=+%28-3%29%28-4%29\"\r
\n" ); document.write( "\n" ); document.write( "Now find the sum of each pair of factors:\r
\n" ); document.write( "\n" ); document.write( "1 + 12 = 13
\n" ); document.write( "2 + 6 = 8
\n" ); document.write( "3 + 4 = 7
\n" ); document.write( "(-1)+(-12) = -13
\n" ); document.write( "(-2)+(-6) = -8
\n" ); document.write( "(-3)+(-4) = -7\r
\n" ); document.write( "\n" ); document.write( "k can be: 13, 8, 7, -13, -8, or -7\r
\n" ); document.write( "\n" ); document.write( "Check:
\n" ); document.write( "\"%28x%2B1%29%28x%2B12%29+=+x%5E2%2B13x%2B12\"
\n" ); document.write( "\"%28x%2B2%29%28x%2B6%29+=+x%5E2%2B8x%2B12\"
\n" ); document.write( "\"%28x%2B3%29%28x%2B4%29+=+x%5E2%2B7x%2B12\"
\n" ); document.write( "\"%28x-1%29%28x-12%29+=+x%5E2-13x%2B12\"
\n" ); document.write( "\"%28x-2%29%28x-6%29+=+x%5E2-8x%2B12\"
\n" ); document.write( "\"%28x-3%29%28x-4%29+=+x%5E2-7x%2B12\"\r
\n" ); document.write( "\n" ); document.write( "You can use the same procedure for \"r%5E2%2Bkr%2B20\"\r
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