document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=192037>Question 192037</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0321279085/algebrahomeworkh>College Algebra with Modeling and Visualization</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Solve the system, if possible\r<BR>\n" );
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document.write( "x - 4y + z= 9<BR>\n" );
document.write( "    3y -2z= -7<BR>\n" );
document.write( "-x      +z= 0\r<BR>\n" );
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document.write( "Worked on these problems for over 3 hours and got nowhere. plase help </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #144107 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=144107\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> x - 4y + z= 9<BR>\n" );
document.write( "0 + 3y -2z= -7<BR>\n" );
document.write( "-x + 0  +z= 0 <BR>\n" );
document.write( "--------------------------<BR>\n" );
document.write( "Add the 1st row to the 3rd to get:<BR>\n" );
document.write( "---<BR>\n" );
document.write( "x - 4y + z = 9<BR>\n" );
document.write( "0 + 3y -2z =-7<BR>\n" );
document.write( "0 + -4y +2z= 9 <BR>\n" );
document.write( "-------------------<BR>\n" );
document.write( "Add the 2nd row to the 3rd row to get:<BR>\n" );
document.write( "x - 4y + z = 9<BR>\n" );
document.write( "0 + 3y -2z =-7<BR>\n" );
document.write( "0 + -y + 0=  2 <BR>\n" );
document.write( "--------------------<BR>\n" );
document.write( "The 3rd row tells you y = -2<BR>\n" );
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document.write( "Substitute into the 2nd row to solve for \"z\":<BR>\n" );
document.write( "3(-2) - 2z = -7<BR>\n" );
document.write( "-6 -2z = -7<BR>\n" );
document.write( "-2z = -1<BR>\n" );
document.write( "z = 1/2<BR>\n" );
document.write( "--------------------------------<BR>\n" );
document.write( "Substitute into the 1st row to solve for \"x\":<BR>\n" );
document.write( "x - 4y + z = 9<BR>\n" );
document.write( "x -4(-2) + (1/2) = 9<BR>\n" );
document.write( "x + 8 1/2 = 9<BR>\n" );
document.write( "x = 1/2<BR>\n" );
document.write( "==================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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