document.write( "Question 148619: I need help solving this problem using the Gaussian Elimination method step by step please!\r
\n" ); document.write( "\n" ); document.write( "4x+3y+2z=6
\n" ); document.write( "-2x-y+5z=5
\n" ); document.write( "x+2y-3z=3\r
\n" ); document.write( "\n" ); document.write( "thank you in advance!
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Algebra.Com's Answer #109055 by Fombitz(32388)\"\" \"About 
You can put this solution on YOUR website!
1.\"4x%2B3y%2B2z=6\"
\n" ); document.write( "2.\"-2x-y%2B5z=5\"
\n" ); document.write( "3.\"x%2B2y-3z=3\"
\n" ); document.write( "Combine equations to remove one of the variables.
\n" ); document.write( "Multiply eq. 2 by (3) and add to eq. 1,
\n" ); document.write( "2.\"3%28-2x-y%2B5z%29=3%285%29\"
\n" ); document.write( "2.\"-6x-3y%2B15z=15\"
\n" ); document.write( "This gets rid of y and makes a new eq. 1 with just x and z,
\n" ); document.write( "1.\"4x%2B3y%2B2z-6x-3y%2B15z=6%2B15\"
\n" ); document.write( "1.\"-2x%2B17z=21\"
\n" ); document.write( "Multiply eq. 2 by (2) and add to eq. 3,
\n" ); document.write( "2.\"2%28-2x-y%2B5z%29=2%285%29\"
\n" ); document.write( "2.\"-4x-2y%2B10z%29=10\"
\n" ); document.write( "This gets rid of y and makes a new eq. 3 with just x and z,
\n" ); document.write( "3.\"x%2B2y-3z-4x-2y%2B10z=3%2B10\"
\n" ); document.write( "3.\"-3x%2B7z=13\"
\n" ); document.write( "Now we have two equations in x and z.
\n" ); document.write( "1.\"-2x%2B17z=21\"
\n" ); document.write( "3.\"-3x%2B7z=13\"
\n" ); document.write( "We can continue to reduce to one variable.
\n" ); document.write( "Multiply eq. 1 by 3 and eq. 3 by -2 and add them to get rid of x,
\n" ); document.write( "1.\"3%28-2x%2B17z%29=3%2821%29\"
\n" ); document.write( "1.\"-6x%2B51z=63\"
\n" ); document.write( "3.\"-2%28-3x%2B7z%29=-2%2813%29\"
\n" ); document.write( "3.\"6x-14z=-26\"
\n" ); document.write( "Now add the two eqs.
\n" ); document.write( "\"-6x%2B51z%2B6x-14z=63-26\"
\n" ); document.write( "\"37z=37\"
\n" ); document.write( "\"z=1\"
\n" ); document.write( "Now that you have z, work backwards and back substitute to find x and then y.
\n" ); document.write( "You can use any of the previous equations to solve for other variables.
\n" ); document.write( "\"-3x%2B7z=13\"
\n" ); document.write( "\"-3x%2B7%281%29=13\"
\n" ); document.write( "\"-3x%2B7=13\"
\n" ); document.write( "\"-3x=6\"
\n" ); document.write( "\"x=-2\"
\n" ); document.write( "And finally for y,
\n" ); document.write( "2.\"-2x-y%2B5z=5\"
\n" ); document.write( "\"-2%28-2%29-y%2B5%281%29=5\"
\n" ); document.write( "\"4-y%2B5=5\"
\n" ); document.write( "\"y=4\"
\n" ); document.write( "(x,y,z)=(-2,4,1)
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