document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=167664>Question 167664</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help!  I am so confused!\r<BR>\n" );
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document.write( "3. Solve for X, Y, and Z in the following systems of three equations:\r<BR>\n" );
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document.write( "a. X + 2Y + Z = 6\r<BR>\n" );
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document.write( "    X + Y  = 4\r<BR>\n" );
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document.write( "    3X + Y + Z =  8\r<BR>\n" );
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document.write( "b. 10X + Y + Z = 12\r<BR>\n" );
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document.write( "    8X + 2Y +Z  = 11\r<BR>\n" );
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document.write( "    20X - 10Y - 2Z = 8\r<BR>\n" );
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document.write( "c. 22X + 5Y + 7Z = 12\r<BR>\n" );
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document.write( "    10X + 3Y + 2Z = 5\r<BR>\n" );
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document.write( "    9X  +  2Y +  12Z = 14 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #123653 by </B><A HREF=/tutors/aboutme.mpl?userid=rviksub><B>rviksub(2)</B></A><img src=\"/images/stars/iconNewId_16x16.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rviksub><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=123653\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a.<BR>\n" );
document.write( "X + 2Y + Z = 6 …………. Equation 1<BR>\n" );
document.write( "X + Y = 4 ……………….. Equation 2<BR>\n" );
document.write( "3X + Y + Z = 8………….. Equation 3\r<BR>\n" );
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document.write( "From Eqn 2, X= 4-Y\r<BR>\n" );
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document.write( "Substitute this value of  X in Eqn 1 and Eqn 1 becomes<BR>\n" );
document.write( "(4-Y)+2Y+Z=6<BR>\n" );
document.write( "» 4+Y+Z=6   i.e., Y+Z=2….Eqn 4\r<BR>\n" );
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document.write( "Substitute the value of Y+Z in Eqn 4 in Eqn 3<BR>\n" );
document.write( "3X+2=8 » 3X=6 » X=2\r<BR>\n" );
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document.write( "Substitute X=2 in Eqn 2<BR>\n" );
document.write( "2+Y=4 <BR>\n" );
document.write( "» Y=2\r<BR>\n" );
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document.write( "Substitute Y=2 in Eqn 4 » Z=0\r<BR>\n" );
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document.write( "b. <BR>\n" );
document.write( "10X + Y + Z = 12 ……… Eqn a<BR>\n" );
document.write( "8X + 2Y +Z = 11 ………. Eqn b<BR>\n" );
document.write( "20X - 10Y - 2Z = 8……... Eqn c\r<BR>\n" );
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document.write( "Eqn. a – Eqn b \r<BR>\n" );
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document.write( "» 2X-Y=1<BR>\n" );
document.write( "Eqn c can be written as 10(2X-Y)-2Z=8<BR>\n" );
document.write( "Substitute 2X-Y=1 in the above eqn<BR>\n" );
document.write( "10(1)-2Z=8 » Z=1<BR>\n" );
document.write( "Substitute Z=1 and Y=2X-1 in eqn a<BR>\n" );
document.write( "10X+2X-1+1=12  » X=1 and Y=2(1)-1=1\r<BR>\n" );
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document.write( "c.<BR>\n" );
document.write( "22X + 5Y + 7Z = 12 ……..Eqn 6<BR>\n" );
document.write( "10X + 3Y + 2Z = 5 ………Eqn 7<BR>\n" );
document.write( "9X + 2Y + 12Z = 14………Eqn 8<BR>\n" );
document.write( "Multiply Eqn 6 by 2 and Eqn 7 by 3 and subtracting them <BR>\n" );
document.write( "X={32(1-Z)}/7…..Eqn 9<BR>\n" );
document.write( "Eqn 6-Eqn7-Eqn8 » 3X-7Z=-7<BR>\n" );
document.write( "Substitute value of X in 3X-7Z=-7 » Z=1<BR>\n" );
document.write( "Substitute Z=1 in Eqn 9 » X=0<BR>\n" );
document.write( "Substitute X=0 and Z=1 in Eqn 6 » Y=1\r<BR>\n" );
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document.write( " </SPAN>\n" );
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