document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=313259>Question 313259</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hello I have a problem, but cant seem to find out what i am doing wrong. The equations are solutions to systems of linear equations in three variables.\r<BR>\n" );
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document.write( "2x+ y-3z=-12<BR>\n" );
document.write( "3x-2y-z=  3<BR>\n" );
document.write( "-x+5y+2z=-3\r<BR>\n" );
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document.write( "I know you have to work only two equations at a time. My teacher took the class through it step by step but i'm thinking im making a mistake on my adding or subtracting because i keep coming out with the wrong answer.<BR>\n" );
document.write( "THanks <BR>\n" );
document.write( "Kayla </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #224007 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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/cgi-bin/show-face.mpl?user=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=224007\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 2x+ y-3z=-12<BR>\n" );
document.write( "3x-2y-z= 3<BR>\n" );
document.write( "-x+5y+2z=-3<BR>\n" );
document.write( "-------------<BR>\n" );
document.write( "To use elimination, pick one of the variables to eliminate.<BR>\n" );
document.write( "I'll eliminate z<BR>\n" );
document.write( "Multiply eqn 2 by 2 and add it to eqn 3.<BR>\n" );
document.write( "Then multiply eqn 2 by 3 and subtract it from eqn 1<BR>\n" );
document.write( "-------------<BR>\n" );
document.write( "3x-2y-z= 3 x2 --> 6x-4y-2z = 6<BR>\n" );
document.write( "-x+5y+2z=-3<BR>\n" );
document.write( "6x-4y-2z = 6<BR>\n" );
document.write( "------------ Add<BR>\n" );
document.write( "5x + y = 3  Eqn A<BR>\n" );
document.write( "----------<BR>\n" );
document.write( "2x+ y-3z=-12<BR>\n" );
document.write( "3x-2y-z= 3 x3 --> 9x-6y-3z = 9<BR>\n" );
document.write( "2x+ y-3z=-12<BR>\n" );
document.write( "9x-6y-3z = 9<BR>\n" );
document.write( "------------ Subtract<BR>\n" );
document.write( "-7x+5y = -21 Eqn B<BR>\n" );
document.write( "--------------------<BR>\n" );
document.write( "Now eqns A and B are in x and y only<BR>\n" );
document.write( "-7x+5y = -21 Eqn B<BR>\n" );
document.write( "25x+5y = 15 Eqn A times 5<BR>\n" );
document.write( "------------ Subtract<BR>\n" );
document.write( "-32x = -36<BR>\n" );
document.write( "x = 9/8<BR>\n" );
document.write( "--------<BR>\n" );
document.write( "Sub for x into Eqn A or B<BR>\n" );
document.write( "5*(9/8) + y = 3<BR>\n" );
document.write( "y = 3 - 45/8<BR>\n" );
document.write( "y = -21/8<BR>\n" );
document.write( "----------<BR>\n" );
document.write( "Sub for x and y into eqn 2 (or any of the original 3)<BR>\n" );
document.write( "3x-2y-z= 3<BR>\n" );
document.write( "3*(9/8) - 2*(-21/8) - z = 3<BR>\n" );
document.write( "z = -3 + 27/8 + 42/8 = -3 + 69/8<BR>\n" );
document.write( "z = 45/8<BR>\n" );
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