document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=106763>Question 106763</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hello I have a substitution problem with 3 equations, there are no examples in my text for a 3 equation using the substitution method to solve when there are missing variables in some of them\r<BR>\n" );
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document.write( "3x +      z=9<BR>\n" );
document.write( " x + 3y    =5<BR>\n" );
document.write( "2x -  y +2z=9\r<BR>\n" );
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document.write( "I have tried everything possible but I just cannot come up with a solution. Can you please help me out? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #77687 by </B><A HREF=/tutors/aboutme.mpl?userid=Earlsdon><B>Earlsdon(6294)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Earlsdon><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=77687\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Solve:<BR>\n" );
document.write( "1) 3x+z = 9 Rewrite this as: z = -3x+9 and substitute into equation 3)<BR>\n" );
document.write( "2) x+3y = 5<BR>\n" );
document.write( "3) 2x-y+2z = 9\r<BR>\n" );
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document.write( "3a) 2x-y+2(-3x+9) = 9 Simplify.<BR>\n" );
document.write( "3a) 2x-y-6x+18 = 9<BR>\n" );
document.write( "3a) -4x-y = -9 Now multiply this equation by 3 and add it to equation 2)\r<BR>\n" );
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document.write( "3b)-12x-3y = -27<BR>\n" );
document.write( "2) x+3y = 5<BR>\n" );
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document.write( "-11x =-22<BR>\n" );
document.write( "x = 2 Substitute this into equation 1) and solve for z.<BR>\n" );
document.write( "1) 3(2)+z = 9<BR>\n" );
document.write( "6+z = 9<BR>\n" );
document.write( "z = 3 Finally, substitute x = 2 and z = 3 into equation 3) and solve for y.<BR>\n" );
document.write( "3) 2(2)-y+2(3) = 9<BR>\n" );
document.write( "4-y+6 = 9<BR>\n" );
document.write( "10-y = 9<BR>\n" );
document.write( "y = 10-9<BR>\n" );
document.write( "y = 1\r<BR>\n" );
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document.write( "Solution: <BR>\n" );
document.write( "x = 2<BR>\n" );
document.write( "y = 1<BR>\n" );
document.write( "z = 3<BR>\n" );
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