document.write( "Question 519029: x+4y-z=7
\n" ); document.write( "x+y+z=2
\n" ); document.write( "-2x-2y+2z=-8\r
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\n" ); document.write( "\n" ); document.write( "convert the system of equations into a matrix equation \n" ); document.write( "

Algebra.Com's Answer #345363 by Edwin McCravy(20060) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "This system\r\n" );
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document.write( "becomes\r\n" );
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document.write( "You didn't say to solve it, but I will anyway, because no doubt\r\n" );
document.write( "you'll be given some later to solve, and you can use this as a\r\n" );
document.write( "model to go by:\r\n" );
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document.write( "To solve it find the inverse of the coefficient matrix, which is\r\n" );
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document.write( "Then left-multiply both sides of the matrix equation by this inverse:\r\n" );
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document.write( "Multiply the first two matrices on the left, and multiply the\r\n" );
document.write( "matrices on the right:\r\n" );
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document.write( "Multiplying the matrices on the left (the one on the left is the identity\r\n" );
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document.write( "So the solution is x=2, y=1, z=-1.\r\n" );
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document.write( "Edwin

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