document.write( "Question 1182830: The positive value of k which will make
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Algebra.Com's Answer #812930 by MathTherapy(10552)\"\" \"About 
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The positive value of k which will make
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\"matrix%281%2C3%2C+4x%5E2+-+4kx+%2B+4k+%2B+5%2C+%22=%22%2C+0%29\"\r\n" );
document.write( "     \"matrix%281%2C3%2C+ax%5E2+%2B+bx+%2B+c%2C+%22=%22%2C+0%29\" <==== Standard form of a quadratic\r\n" );
document.write( "By EQUATING terms, we see that: \r\n" );
document.write( "                                \"highlight%28a%29x%5E2\"+  \"highlight%28b%29x\"+  \"highlight%28c%29\"  =  0\r\n" );
document.write( "              Therefore, we get: a = 4\r\n" );
document.write( "                                 b = - 4k\r\n" );
document.write( "                                 c = + 4k + 5 \r\n" );
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document.write( "                                  \r\n" );
document.write( "In order for the polynomial to be a PERFECT SQAURE, the discriminant (b2 - 4ac) MUST = 0. \r\n" );
document.write( "                    We then get: \r\n" );
document.write( "                                        (k - 5)(k + 1) = 0\r\n" );
document.write( "                                    k - 5 = 0    OR      k + 1 = 0\r\n" );
document.write( "                                        k = 5    OR         k = - 1\r\n" );
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document.write( "Since a  POSITIVE value for k is required, the ONLY ANSWER is: \"highlight_green%28matrix%281%2C3%2C+k%2C+%22=%22%2C+5%29%29\"
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