document.write( "Question 1140461: Use a matrix approach to solve the system. Express the solutions as 4-tuples of the form
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\n" ); document.write( "x1 − 3x2 − 2x3 + x4 = −2
\n" ); document.write( "−2x1 + 7x2 + x3 − 2x4 = −3
\n" ); document.write( "3x1 − 7x2 − 3x3 + 3x4 = −2
\n" ); document.write( "5x1 + x2 + 4x3 − 2x4 = 16
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Algebra.Com's Answer #760996 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
\"x%5B1%5D+-+3x%5B2%5D+-+2x%5B3%5D+%2B+x4%09=+-2\"
\n" ); document.write( "\"-2x%5B1%5D+%2B+7x%5B2%5D+%2B+x%5B3%5D+-+2x%5B4%5D%09=+-3\"
\n" ); document.write( "\"3x%5B1%5D+-+7x%5B2%5D+-+3x%5B3%5D+%2B+3x%5B4%5D%09=+-2\"
\n" ); document.write( "\"5x%5B1+%5D%2B+x%5B2+%5D%2B+4x%5B3%5D+-2x%5B4%5D%09=+16\"\r
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\n" ); document.write( "\n" ); document.write( "your matrix:\r
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\n" ); document.write( "\n" ); document.write( "Find the pivot in the 1st column in the 1st row:\r
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\n" ); document.write( "\n" ); document.write( "Eliminate the 1st column:\r
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\n" ); document.write( "\n" ); document.write( "Find the pivot in the 2nd column in the 2nd row:\r
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\n" ); document.write( "\n" ); document.write( "Eliminate the 2nd column:\r
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\n" ); document.write( "\n" ); document.write( "Make the pivot in the 3rd column by dividing the 3rd row by \"9\":\r
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\n" ); document.write( "\n" ); document.write( "Eliminate the 3rd column\r
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\n" ); document.write( "\n" ); document.write( "Make the pivot in the 4th column by dividing the 4th row by \"-7\":\r
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\n" ); document.write( "\n" ); document.write( "Eliminate the 4th column:\r
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\n" ); document.write( "\n" ); document.write( "Solution set:\r
\n" ); document.write( "\n" ); document.write( "\"x%5B1%5D+=+1\"
\n" ); document.write( "\"x%5B2+%5D=+-1\"
\n" ); document.write( "\"x%5B3%5D+=+2\"
\n" ); document.write( "\"x%5B4%5D+=+-2\"\r
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