document.write( "Question 922594: Solve the system of equations\r
\n" ); document.write( "\n" ); document.write( "3x+4y+z=7
\n" ); document.write( " 2y+z=3
\n" ); document.write( "-5x+3y+8z=-31\r
\n" ); document.write( "\n" ); document.write( "Please Help
\n" ); document.write( "

Algebra.Com's Answer #559629 by MathLover1(20849)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"3x%2B4y%2Bz=7\"......eq.1
\n" ); document.write( "\"2y%2Bz=3\".........eq.2
\n" ); document.write( "\"-5x%2B3y%2B8z=-31\"......eq.3
\n" ); document.write( "__________________________________\r
\n" ); document.write( "\n" ); document.write( "\"+2y%2Bz=3\"......eq.2 ...solve for \"z\"\r
\n" ); document.write( "\n" ); document.write( "\"z=3-+2y\"\r
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\n" ); document.write( "\n" ); document.write( "\"3x%2B4y%2Bz=7\"......eq.1...plug in \"z\"\r
\n" ); document.write( "\n" ); document.write( "\"3x%2B4y%2B3-2y=7\"\r
\n" ); document.write( "\n" ); document.write( "\"3x%2B2y=7-3\"\r
\n" ); document.write( "\n" ); document.write( "\"3x%2B2y=4\"......solve for \"x\"\r
\n" ); document.write( "\n" ); document.write( "\"3x=4-2y\"\r
\n" ); document.write( "\n" ); document.write( "\"x=4%2F3-2y%2F3\"\r
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\n" ); document.write( "\n" ); document.write( "\"-5x%2B3y%2B8z=-31\"......eq.3..plug in \"z\" and \"x\"\r
\n" ); document.write( "\n" ); document.write( "\"-5%284%2F3-2y%2F3%29%2B3y%2B8%283-+2y%29=-31\"...solve for \"y\"\r
\n" ); document.write( "\n" ); document.write( "\"-20%2F3%2B10y%2F3%2B3y%2B24-+16y=-31\"...both sides multiply by \"3\"\r
\n" ); document.write( "\n" ); document.write( "\"-20%2B10y%2B9y%2B72-+48y=-93\"\r
\n" ); document.write( "\n" ); document.write( "\"19y-48y=-93%2B20-72\"\r
\n" ); document.write( "\n" ); document.write( "\"-29y=-145\".....both sides multiply by \"-1\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"29y=145\"\r
\n" ); document.write( "\n" ); document.write( "\"y=145%2F29\"\r
\n" ); document.write( "\n" ); document.write( "\"highlight%28y=5%29\"\r
\n" ); document.write( "\n" ); document.write( "go to \"z=3-+2y\" plug in \"y\"\r
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\n" ); document.write( "\n" ); document.write( "\"z=3-+2%2A5\"\r
\n" ); document.write( "\n" ); document.write( "\"z=3-+10\"\r
\n" ); document.write( "\n" ); document.write( "\"highlight%28z=-7%29\"\r
\n" ); document.write( "\n" ); document.write( "go to \"x=4%2F3-2y%2F3\" plug in \"y\"\r
\n" ); document.write( "\n" ); document.write( "\"x=4%2F3-%282%2A5%29%2F3\"\r
\n" ); document.write( "\n" ); document.write( "\"x=4%2F3-10%2F3\"\r
\n" ); document.write( "\n" ); document.write( "\"x=-6%2F3\"\r
\n" ); document.write( "\n" ); document.write( "\"highlight%28x=-2%29\"\r
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\n" ); document.write( "\n" ); document.write( "so, \"highlight%28x=-2%29\", \"highlight%28y=5%29\", and \"highlight%28z=-7%29\"\r
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\n" ); document.write( "\n" ); document.write( "check: \r
\n" ); document.write( "\n" ); document.write( "\"3x%2B4y%2Bz=7\"......eq.1\r
\n" ); document.write( "\n" ); document.write( "\"3%28-2%29%2B4%2A5%2B%28-7%29=7\" \r
\n" ); document.write( "\n" ); document.write( "\"-6%2B20-7=7\"\r
\n" ); document.write( "\n" ); document.write( "\"20-13=7\"\r
\n" ); document.write( "\n" ); document.write( "\"7=7\"
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