document.write( "Question 192037This question is from textbook College Algebra with Modeling and Visualization
\n" ); document.write( ": Solve the system, if possible\r
\n" ); document.write( "\n" ); document.write( "x - 4y + z= 9
\n" ); document.write( " 3y -2z= -7
\n" ); document.write( "-x +z= 0\r
\n" ); document.write( "\n" ); document.write( "Worked on these problems for over 3 hours and got nowhere. plase help \n" ); document.write( "
Algebra.Com's Answer #144114 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
Solve the system, if possible
\n" ); document.write( "x - 4y + z= 9
\n" ); document.write( "3y -2z= -7
\n" ); document.write( "-x +z= 0
\n" ); document.write( ";
\n" ); document.write( "let's rewrite it and add:
\n" ); document.write( "x - 4y + z = 9
\n" ); document.write( "0x +3y -2z = -7
\n" ); document.write( "-x +0y + z = 0
\n" ); document.write( "----------------Addition eliminates x and z
\n" ); document.write( "-y = 2
\n" ); document.write( "y = -2
\n" ); document.write( ":
\n" ); document.write( "Find z using the 2nd original equation
\n" ); document.write( "3(-2) - 2z = -7
\n" ); document.write( "-6 - 2z = -7
\n" ); document.write( "-2z = -7 + 6
\n" ); document.write( "-2z = -1
\n" ); document.write( "z = \"%28-1%29%2F%28-2%29\"
\n" ); document.write( "z = +.5
\n" ); document.write( ";
\n" ); document.write( "Find x using the last original equation:
\n" ); document.write( "-x + .5 = 0
\n" ); document.write( "-x = -.5
\n" ); document.write( "x = + .5
\n" ); document.write( ":
\n" ); document.write( "Solutions: x=.5; y=-2; z=.5
\n" ); document.write( ":
\n" ); document.write( "Check solution in 1st original equation x - 4y + z = 9
\n" ); document.write( ".5 - 4(-2) + .5 = 9
\n" ); document.write( ".5 + 8 + .5 = 9
\n" ); document.write( " \n" ); document.write( "
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