document.write( "Question 1101285: Solve the System By Substitution\r
\n" ); document.write( "\n" ); document.write( "- x - y - z = - 8
\n" ); document.write( "-4x + 4y + 5z = 7
\n" ); document.write( "2x + 2z = 4\r
\n" ); document.write( "\n" ); document.write( "A step-by-step explanation would be greatly appreciated. Thank you :) \n" ); document.write( "
Algebra.Com's Answer #715852 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "\"system%28-x+-+y+-+z+=+-+8%2C-4x+%2B+4y+%2B+5z+=+7%2C2x+%2B+2z+=+4%29\"\r\n" );
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document.write( "Solve \"2x+%2B+2z+=+4\" for x\r\n" );
document.write( "      \"2x+=+4-2z\"\r\n" );
document.write( "      \"x+=+2-z\"\r\n" );
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document.write( "Substitute 2-z for x in \"-x+-+y+-+z+=+-8\"\r\n" );
document.write( "                        \"-%282-z%29+-+y+-+z+=+-8\"\r\n" );
document.write( "                        \"-2%2Bz-y-z+=+-8\" \r\n" );
document.write( "                        \"-2-y+=+-8\"  \r\n" );
document.write( "                        \"-y+=+-6\"\r\n" );
document.write( "                        \"y+=+6\"\r\n" );
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document.write( "Substitute 2-z for x and 6 for y in the only equation\r\n" );
document.write( "we haven't used, which is  \"-4x+%2B+4y+%2B+5z+=+7\"\r\n" );
document.write( "                           \"-4%282-z%29+%2B+4%286%29+%2B+5z+=+7\"\r\n" );
document.write( "                           \"-8%2B4z+%2B+24+%2B+5z+=+7\"\r\n" );
document.write( "                           \"9z+%2B+16+=+7\"\r\n" );
document.write( "                           \"9z+=+-9\"\r\n" );
document.write( "                           \"z+=+-1\"\r\n" );
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document.write( "Finally find x by substituting -1 for z in \"x+=+2-z\"\r\n" );
document.write( "                                           \"x+=+2-%28-1%29\" \r\n" );
document.write( "                                           \"x=2%2B1\"\r\n" );
document.write( "                                           \"x=3\" \r\n" );
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document.write( "          (x,y,z) = (3,6,-1)\r\n" );
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document.write( "Edwin
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