document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=174510>Question 174510</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 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<BR>\n" );
document.write( "    X + Y  = 4<BR>\n" );
document.write( "    3X + Y + Z =  8\r<BR>\n" );
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document.write( "b. 10X + Y + Z = 12<BR>\n" );
document.write( "    8X + 2Y +Z  = 11<BR>\n" );
document.write( "    20X - 10Y - 2Z = 8\r<BR>\n" );
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document.write( "c. 22X + 5Y + 7Z = 12<BR>\n" );
document.write( "    10X + 3Y + 2Z = 5<BR>\n" );
document.write( "    9X  +  2Y +  12Z = 14<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #129516 by </B><A HREF=/tutors/aboutme.mpl?userid=checkley77><B>checkley77(12844)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=checkley77><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=129516\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a. <BR>\n" );
document.write( "X + 2Y + Z = 6<BR>\n" );
document.write( "X + Y  = 4 or x=4-y. Now replace x with (4-y) in the first & third equations & subtract them.<BR>\n" );
document.write( "3X + Y + Z =  8<BR>\n" );
document.write( "3(4-y)+y+z=8<BR>\n" );
document.write( "-[(4-y)+2y+z=6] now subtract.<BR>\n" );
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document.write( "12-3y+y-4+y-2y=8-6<BR>\n" );
document.write( "-3y+8=2<BR>\n" );
document.write( "-3y=2-8<BR>\n" );
document.write( "-3y=-6<BR>\n" );
document.write( "y=-6/-3<BR>\n" );
document.write( "y=2 ans.<BR>\n" );
document.write( "x+2=4<BR>\n" );
document.write( "x=4-2<BR>\n" );
document.write( "x=2 ans.<BR>\n" );
document.write( "3*2+2+z=8<BR>\n" );
document.write( "6+2+z=8<BR>\n" );
document.write( "z=8-8<BR>\n" );
document.write( "z=0 ans.<BR>\n" );
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document.write( "b. 10X + Y + Z = 12<BR>\n" );
document.write( "    8X + 2Y +Z  = 11<BR>\n" );
document.write( "    20X - 10Y - 2Z = 8 add all 3 equations.<BR>\n" );
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document.write( "38X-7Y=31<BR>\n" );
document.write( "NOW SUBTRACT EQUATION 2 FROM EQUATION 1.<BR>\n" );
document.write( "10X+Y+Z=12<BR>\n" );
document.write( "-(8X+2Y+Z=11)<BR>\n" );
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document.write( "2X-Y=1 NOW MULTIPLY THIS EQUATION BY -7 & ADD THEM.<BR>\n" );
document.write( "-14X+7Y=-7<BR>\n" );
document.write( "38X-7Y=31<BR>\n" );
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document.write( "24X=24<BR>\n" );
document.write( "X=24/24<BR>\n" );
document.write( "X=1 ans.<BR>\n" );
document.write( "2*1-Y=1<BR>\n" );
document.write( "2-Y=1<BR>\n" );
document.write( "-Y=1-2<BR>\n" );
document.write( "-Y=-1<BR>\n" );
document.write( "Y=1 ans.<BR>\n" );
document.write( "10*1+1+Z=12<BR>\n" );
document.write( "10+1+Z=12<BR>\n" );
document.write( "11+Z=12<BR>\n" );
document.write( "Z=12-11<BR>\n" );
document.write( "Z=1 ans.<BR>\n" );
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document.write( "I'LL LEAVE THE REST FOR YOU TO PRACTICE WITH.<BR>\n" );
document.write( "c. 22X + 5Y + 7Z = 12<BR>\n" );
document.write( "    10X + 3Y + 2Z = 5<BR>\n" );
document.write( "    9X  +  2Y +  12Z = 14<BR>\n" );
document.write( " </SPAN>\n" );
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