document.write( "Question 791782: What would be the easiest way to solve this problem ? The only known value is that z=9\r
\n" ); document.write( "\n" ); document.write( "x + Y + Z = 14
\n" ); document.write( "x - 2y = -4
\n" ); document.write( "Z = 9
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Algebra.Com's Answer #479722 by solver91311(24713)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "You cannot find a unique solution to the problem as written. Y is NOT, under any circumstances the same thing as y. Hence you have four variables and only three equations, so the best you can do is find a relative solution.\r
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\n" ); document.write( "\n" ); document.write( "On the other hand, if you really meant:\r
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\n" ); document.write( "\n" ); document.write( "Then substitute 9 for in equation 1 to get:\r
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\n" ); document.write( "\n" ); document.write( "Leaving you with the 2X2 system:\r
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\n" ); document.write( "\n" ); document.write( "Multiply the 2nd equation by -1.\r
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\n" ); document.write( "\n" ); document.write( "Add the two equations:\r
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\n" ); document.write( "\n" ); document.write( "Substitute back into\r
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\n" ); document.write( "\n" ); document.write( "The solution set is \r
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\n" ); document.write( "My calculator said it, I believe it, that settles it
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