document.write( "Question 1159515: Find k such that the matrix, M =
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Algebra.Com's Answer #782559 by ikleyn(52805)\"\" \"About 
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document.write( "Let the rows of the given matrix be  E1,  E2  and E3, counting from the top to the bottom.\r\n" );
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document.write( "Notice that the row  2E1 - E2 is equal to\r\n" );
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document.write( "    [-9,  -2,  -11].\r\n" );
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document.write( "It will be exactly equal to the third row,  E3,  if  -9 = -6+k, i.e. k= -3.\r\n" );
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document.write( "Then the determinant of the matrix will be zero.\r\n" );
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document.write( "ANSWER.  k = -3.\r\n" );
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