document.write( "Question 792999: Find all positive integral values of \"k\" for which the trinomial can be factored.\r
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Algebra.Com's Answer #480200 by Edwin McCravy(20055)\"\" \"About 
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document.write( "y²+8y+k\r\n" );
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document.write( "Suppose it factors as\r\n" );
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document.write( "(y+a)(y+b) where a and b are positive integers.\r\n" );
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document.write( "Then FOIL-ing that out,\r\n" );
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document.write( "y²+by+ay+ab\r\n" );
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document.write( "Factor y out of the middle two terms:\r\n" );
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document.write( "y²+(b+a)y+ab\r\n" );
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document.write( "Compare that to \r\n" );
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document.write( "y²+8y+k\r\n" );
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document.write( "So the coefficient of y which is b+a=8, and the last term ab=k\r\n" );
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document.write( "b   a   b+a   ab=k       factorization\r\n" );
document.write( "1   7    8     7=k    y²+8y+7 = (y+1)(y+7)\r\n" );
document.write( "2   6    8    12=k   y²+8y+12 = (y+2)(y+6)\r\n" );
document.write( "3   5    8    15=k   y²+8y+15 = (y+3)(y+5)\r\n" );
document.write( "4   4    8    16=k   y²+8y+16 = (y+4)(y+4) = (y+4)²\r\n" );
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document.write( "Answer: all positive integral valuse for k are 7,12,15, and 16\r\n" );
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document.write( "Now you do the other one the same way.\r\n" );
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document.write( "Edwin
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