document.write( "Question 182077: Matrices
\n" ); document.write( "Hello I'm needing some help with my homework that asks me to use the matrices to solve each system of equations. If a system has no solution, so indicate. \r
\n" ); document.write( "\n" ); document.write( "{x-y+z=2
\n" ); document.write( " x+2y-z=6
\n" ); document.write( " 2x-y-z=3\r
\n" ); document.write( "\n" ); document.write( "thanks\r
\n" ); document.write( "\n" ); document.write( "Haley
\n" ); document.write( "

Algebra.Com's Answer #136668 by Alan3354(69443)\"\" \"About 
You can put this solution on YOUR website!
|x - y + z 2|
\n" ); document.write( "|x +2y - z 6| = 0
\n" ); document.write( "|2x -y - z 3|
\n" ); document.write( "---------------
\n" ); document.write( "You can leave out the x, y and z.
\n" ); document.write( "|1 -1 +1 2|
\n" ); document.write( "|1 +2 -1 6| = 0
\n" ); document.write( "|2 -1 -1 3|
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\n" ); document.write( "First, find the determinant.
\n" ); document.write( "DET = 1*(-2-1) + 1*(-1+2) + 1*(-1-4) = -3+1-5
\n" ); document.write( "DET = -7
\n" ); document.write( "-----------
\n" ); document.write( "x*DET = -1(-3+6) -1(6+6) +2(-2-1) =-3-12-6 = -21
\n" ); document.write( "x = 3
\n" ); document.write( "-----------
\n" ); document.write( "-y*DET = 1(-3+6) -1(3-12) +2(-1+2) = 3+9+2 = 14
\n" ); document.write( "y = 2
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\n" ); document.write( "At this point, I'd substitute to find z, but it says use a matrix.
\n" ); document.write( "z*DET = 1(6+6) +1(3-12) +2(-1-4) = 12-9-10 = -7
\n" ); document.write( "z = 1
\n" ); document.write( "----------
\n" ); document.write( "You can find solvers online to do these, or you can do them with an Excel sheet.
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