document.write( "Question 235116: 
its a question on multiplying matrices.\r\n" );
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document.write( "(2X3)  [4  -2   -7]    [-2 ](3X1 matrice)\r\n" );
document.write( "       [6   3    5]    [ 5 ]\r\n" );
document.write( "                       [ 3 ]
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Algebra.Com's Answer #173293 by Edwin McCravy(20064)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "When you multiply a (2x3) matrix by a (3x1) matrix, you \r\n" );
document.write( "first find out what kind of matrix you're going to get\r\n" );
document.write( "by this method:\r\n" );
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document.write( "(\"2\"x\"3\") by (\"3\"x\"1\")\r\n" );
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document.write( "Cross out the inner dimensions, which must be the same:\r\n" );
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document.write( "(\"2\"x\"cross%283%29\") by (\"cross%283%29\"x\"1\")\r\n" );
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document.write( "and you get a \r\n" );
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document.write( "\"2\"x\"1\" matrix.\r\n" );
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document.write( "So we write this with a {2x1) matrix with\r\n" );
document.write( "question marks for elements\r\n" );
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document.write( "To get what goes in place of the 1st question mark,\r\n" );
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document.write( "Multiply each element in the 1st row of the (2x3) matrix\r\n" );
document.write( "by the corresponding element in the (3x1), then add,\r\n" );
document.write( "like this:\r\n" );
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document.write( "\"%284%29%28-2%29%2B%28-2%29%285%29%2B%28-7%29%283%29=-8-10-21=-39\", so we have\r\n" );
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document.write( "-------------------\r\n" );
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document.write( "To get what goes in place of the 2nd question mark,\r\n" );
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document.write( "Multiply each element in the 2nd row of the (2x3) matrix\r\n" );
document.write( "by the corresponding element in the (3x1), then add,\r\n" );
document.write( "like this:\r\n" );
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document.write( "\"%286%29%28-2%29%2B%283%29%285%29%2B%285%29%283%29=-12%2B15%2B15=18\", so we have\r\n" );
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document.write( "-------------------\r\n" );
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document.write( "Edwin
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