document.write( "Question 44751: equations with 3 linear variables\r
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document.write( "6x-4y+5z=31
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document.write( "5x+2y+2z=13
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document.write( "x+y+z=2\r
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document.write( "should you multiply the 2nd equation by 2?\r
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document.write( "show work \n" );
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Algebra.Com's Answer #29601 by venugopalramana(3286)![]() ![]() You can put this solution on YOUR website! OK..THE PROBLEM,WE FACE IN ANSWERING IS THAT WE ARE NOT AWARE OF YOUR COURSE OF STUDY AND BACKGROUND.THE SOLUTION I GAVE IS BY GAUSS JORDAN ELIMINATION METHOD USED IN MATRICES AS WANTED BY SOME STUDENTS.IF YOU ARE NOT TAUGHT THAT ,WE SHALL DO BY NORMAL ELIMINATION.\r \n" ); document.write( "\n" ); document.write( "equations with 3 linear variables \n" ); document.write( "6x-4y+5z=31.......................................I \n" ); document.write( "5x+2y+2z=13...........................II \n" ); document.write( "x+y+z=2.......................III \n" ); document.write( "EQN.II - 2*EQN.III \n" ); document.write( "5X+2Y+2Z-2X-2Y-2Z=13-2*2=9 \n" ); document.write( "3X=9 \n" ); document.write( "X=9/3=3 \n" ); document.write( "EQN.I+4*EQN.III \n" ); document.write( "6X-4Y+5Z+4X+4Y+4Z=31+4*2=39 \n" ); document.write( "10X+9Z=39...BUT...X=3..SO \n" ); document.write( "10*3+9Z=39 \n" ); document.write( "9Z=39-30=9 \n" ); document.write( "Z=9/9=1 \n" ); document.write( "PUTTING IN EQN.III \n" ); document.write( "3+Y+1=2 \n" ); document.write( "Y=2-4=-2 \n" ); document.write( "HOPE YOU UNDERSTOOD. \n" ); document.write( "------------------------------------------------------------------------ \n" ); document.write( "SEE THE FOLLOWING AND TRY.IF STILL IN DIFFICULTY PLEASE COME BACK \n" ); document.write( "YOU MAY MULTIPLY EQN.II WITH 2 AND ADD TO EQN.I TO ELIMINATE Y \n" ); document.write( "x - y + z = 2 \n" ); document.write( "-x + y + z = 4 \n" ); document.write( "-x + z = 2 \n" ); document.write( "augmented matrix is \n" ); document.write( "1.....................-1.......................1.............................2 \n" ); document.write( "-1.....................1.......................1.............................4 \n" ); document.write( "-1.....................0.......................1.............................2 \n" ); document.write( "nr2=r2+r1 and nr3=r3+r1 \n" ); document.write( "1..................-1.................1.............2 \n" ); document.write( "1-1=0............1-1=0............1+1=2..........2+4=6 \n" ); document.write( "1-1=0...........-1+0=-1...........1+1=2..........2+2=4 \n" ); document.write( "nr2=r2/2....nr3=r3-r2 \n" ); document.write( "1....................-1...............1..............2 \n" ); document.write( "0/2=0.............0/2=0..............2/2=1........6/2=3 \n" ); document.write( "0-0=0............-1-0=-1..............2-2=0.......4-6=-2 \n" ); document.write( "nr1=r1-r3-r2.......nr2=2r2........nr3=-r3 \n" ); document.write( "1-0-0=1............-1+1-0=0.........1-0-1=0.......2+2-3=1 \n" ); document.write( "0.....................0...................1............3 \n" ); document.write( "0.....................1...................0.............2 \n" ); document.write( "exchange r2 and r3 \n" ); document.write( "1....0........0.......1 \n" ); document.write( "0....1........0.......2 \n" ); document.write( "0....0........1.......3 \n" ); document.write( "he\r \n" ); document.write( "\n" ); document.write( "nce x=1......y=2.....z=3 \n" ); document.write( " |