document.write( "Question 29946: I am so confused as to how to figured out a matrix problem using the Gauss-Jordan Method.
\n" ); document.write( "Problem:
\n" ); document.write( "3X-2Y=-8Z+9
\n" ); document.write( "-2X+Z=-2Y+3
\n" ); document.write( "2Y-3Z+X=8\r
\n" ); document.write( "\n" ); document.write( "Thanks!!!!
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Algebra.Com's Answer #18004 by brianunlv(12)\"\" \"About 
You can put this solution on YOUR website!
system of equations we have:
\n" ); document.write( "+3x - 2y + 8z = 9
\n" ); document.write( "-2x + 2y + z = 3
\n" ); document.write( " +x + 2y - 37 = 8
\n" ); document.write( "in equation form:
\n" ); document.write( "-
\n" ); document.write( "|3 -2 8 |x|`|9|
\n" ); document.write( "|-2 2 1 |y|=|3|
\n" ); document.write( "|1 2 -3 |z|`|8|
\n" ); document.write( "-
\n" ); document.write( "in matrix form:
\n" ); document.write( "-
\n" ); document.write( "|3 -2 8 |9||x|
\n" ); document.write( "|-2 2 1 |3||y|
\n" ); document.write( "|1 2 -3 |8||z|
\n" ); document.write( "-
\n" ); document.write( "first do gauss elemination (bottum left triangle = 0):
\n" ); document.write( "1.switch row1(R1) with row3(R3):
\n" ); document.write( "-
\n" ); document.write( "|1 2 -3 |8||x|
\n" ); document.write( "|-2 2 1 |3||y|
\n" ); document.write( "|3 -2 8 |9||z|
\n" ); document.write( "-
\n" ); document.write( "2.subtract 3*(R1) from (R3):
\n" ); document.write( "-
\n" ); document.write( "|1 2 -3 |8||x|
\n" ); document.write( "|-2 2 1 |3||y|
\n" ); document.write( "|0 -8 17 |-15||z|
\n" ); document.write( "-
\n" ); document.write( "3.subtract -4*(R1) from (R3):
\n" ); document.write( "-
\n" ); document.write( "|1 2 -3 |8||x|
\n" ); document.write( "|-2 2 1 |3||y|
\n" ); document.write( "|0 0 5 |9||z|--->we can see z = 9/5 already
\n" ); document.write( "-
\n" ); document.write( "4.subtract -2*(R1) from (R2):
\n" ); document.write( "-
\n" ); document.write( "|1 2 -3 |8||x|
\n" ); document.write( "|0 6 -5 |19||y|
\n" ); document.write( "|0 0 5 |9||z|
\n" ); document.write( "-
\n" ); document.write( "Now do jordan elemination (top right triangle = 0):
\n" ); document.write( "1. subtract -5/3*(R1) from (R2):
\n" ); document.write( "-
\n" ); document.write( "|1 2 -3 |8||x|
\n" ); document.write( "|0 6 0 |97/3||y|--->we can see y = (97/3)/6 already
\n" ); document.write( "|0 0 5 |9||z|
\n" ); document.write( "-
\n" ); document.write( "2. So we can now find x with back substitution:
\n" ); document.write( " x + 2((97/3)/6) - 3(9/5) = 8
\n" ); document.write( " x + (1164/3) - (27/5) = 8
\n" ); document.write( "x + 382 3/5 = 8
\n" ); document.write( "x = 8 - 382 3/5
\n" ); document.write( "x = 374 3/5\r
\n" ); document.write( "\n" ); document.write( "Regards,
\n" ); document.write( "Brian Bird\r
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