document.write( "Question 1134370: 3x-y-2z= 18
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Algebra.Com's Answer #751740 by Edwin McCravy(20059) $\"\"$ $\"About$

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document.write( "Pick a pair of equations and a letter to eliminate.\r\n" );
document.write( "[Note: There are 6 different ways to start, all correct!]\r\n" );
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document.write( "I will pick the first two equations and y to eliminate,\r\n" );
document.write( "because it happens to be the easiest because all you have to\r\n" );
document.write( "do is add them and y will be eliminated:\r\n" );
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document.write( "Now pick a different pair of equations and eliminate the\r\n" );
document.write( "SAME letter eliminated first. \r\n" );
document.write( "[Note: we have to pick one of the same equations again, but\r\n" );
document.write( "we must pick the third equation this time.]\r\n" );
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document.write( "So I will pick the first and third equations and y to eliminate:\r\n" );
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document.write( "To eliminate y we multiply the first equation through by 3\r\n" );
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document.write( "Now we have 2 equations in 2 letters to solve:\r\n" );
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document.write( "We can eliminate x by multiplying the first equation through by -2\r\n" );
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document.write( "Substitute that in \r\n" );
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document.write( "Substitute z=-2 and x=5 in any one of the original equations:\r\n" );
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document.write( "Answer: (x,y,z) = (5,1,-2)\r\n" );
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document.write( "Edwin

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