document.write( "Question 1091559: 2x+y-z=20
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Algebra.Com's Answer #706009 by ikleyn(52879)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "2x +  y - z = 20    (1)\r\n" );
document.write( " x + 3y     = 13    (2)\r\n" );
document.write( " x          =  3    (3)\r\n" );
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document.write( "The equation (3) just gives you the solution for x:  x = 3.\r\n" );
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document.write( "Substitute it into equation (2).  You will get\r\n" );
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document.write( " 3 + 3y = 13  ====>  3y = 13 - 3 = 10  ===>  y = \"10%2F3\" = \"3\" \"1%2F3\".\r\n" );
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document.write( "Thus you found the unknown y, too.\r\n" );
document.write( "Now substitute x = 3, y = \"10%2F3\" into equation (1).  You will get\r\n" );
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document.write( "\"20%2F3+%2B+3+-z\" = 20  ====>  z = \"20+-+3+-+20%2F3\" = \"17\" - \"6\" \"2%2F3\" = \"10\" \"1%2F3\".\r\n" );
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document.write( "Answer.  x = 3,  y = \"3\" \"1%2F3\",  z = \"10\" \"1%2F3\".\r\n" );
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\n" ); document.write( "\n" ); document.write( "Ignore writing by @josgarithmetic, because it leads you in wrong direction.\r
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