document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=50099>Question 50099</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Well I will start off saying I know I have the wrong answer somewhere and I know that because I put my answers into the original equations and they don't work. I have trouble when you throw that third variable in so if someone can tell what is right (if anything) and where I went wrong. Thanks!! Andrea \r<BR>\n" );
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document.write( "(a) <BR>\n" );
document.write( "2x – y + z = 8 <BR>\n" );
document.write( "x + 2y + z = -3 <BR>\n" );
document.write( "x - 2y – z = 7 \r<BR>\n" );
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document.write( "(1 & 3) <BR>\n" );
document.write( "3x – 3y = 15 <BR>\n" );
document.write( "x – y = 5 \r<BR>\n" );
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document.write( "2x = 4 <BR>\n" );
document.write( "x = 2 \r<BR>\n" );
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document.write( "2 – y = 5 <BR>\n" );
document.write( "y = -3 \r<BR>\n" );
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document.write( "2 + 2(-3) + z = -3 <BR>\n" );
document.write( "z = 1 \r<BR>\n" );
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document.write( "(b) <BR>\n" );
document.write( "3x - y - 2z = 11 <BR>\n" );
document.write( "x – 2y + 3z = 12 <BR>\n" );
document.write( "x + y - 2z = 5 \r<BR>\n" );
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document.write( "(1 & 3) = (4) <BR>\n" );
document.write( "4x – 4z = 16 \r<BR>\n" );
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document.write( "(2 & 3) = (5) <BR>\n" );
document.write( "x – 2y + 3z = 12 <BR>\n" );
document.write( "2x + 2y – 4z = 10 <BR>\n" );
document.write( "3x + z = 22 \r<BR>\n" );
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document.write( "(4 & 5) <BR>\n" );
document.write( "4x – 4z = 16 <BR>\n" );
document.write( "3x + z = 22 \r<BR>\n" );
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document.write( "4x – 4z = 16 <BR>\n" );
document.write( "-12x + 4z = -88 <BR>\n" );
document.write( "-8x = -72 <BR>\n" );
document.write( "x = 9 \r<BR>\n" );
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document.write( "3(9) + z = 22 <BR>\n" );
document.write( "27 + z = 22 <BR>\n" );
document.write( "z = -5 \r<BR>\n" );
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document.write( "9 – y – 2(-5) = 5 <BR>\n" );
document.write( "9 – y + 10 = 5 <BR>\n" );
document.write( "19 – y = 5 <BR>\n" );
document.write( "-y = -14 <BR>\n" );
document.write( "y = 14 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #33262 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=33262\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Ok, there's nothing wrong with your solution to problem a), but the solution to problem b) is another story. Let's have a look:\r<BR>\n" );
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document.write( "b)<BR>\n" );
document.write( "1) 3x-y-2z = 11<BR>\n" );
document.write( "2) x-2y+3z = 12<BR>\n" );
document.write( "3) x+y-2z = 5<BR>\n" );
document.write( "Add 1) & 3)<BR>\n" );
document.write( "4) 4x-4z = 16 You are ok here.<BR>\n" );
document.write( "4a) x-z = 4   You are ok here.\r<BR>\n" );
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document.write( "Now add 2) and 2 X 3)<BR>\n" );
document.write( "2) x-2y+3z = 12<BR>\n" );
document.write( "3a) 2x+2y-4z = 10 adding theses two, you get (or should have obtained)<BR>\n" );
document.write( "5) 3x-z = 22 Here's one of your boo boo's (3z+(-4z) = -z...not +z as you had)<BR>\n" );
document.write( " Now here you could have subtracted 4a) from 5) to get x.<BR>\n" );
document.write( "4a) x-z = 4<BR>\n" );
document.write( "5) 3x-z = 22<BR>\n" );
document.write( "6) 2x = 18<BR>\n" );
document.write( "6a) x = 9 ...and you got this right!\r<BR>\n" );
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document.write( "Now to find z. You can substitute x = 9 into 4a.<BR>\n" );
document.write( "4b) 9-z = 4 Solve for z.<BR>\n" );
document.write( "4c) z = 5 Here's another boo boo, you had z = -5\r<BR>\n" );
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document.write( "To find y, substitute x = 9 and z = 5 into any of your original equations and solve for y. Let's use equation 1)<BR>\n" );
document.write( "3x-y-2z = 11<BR>\n" );
document.write( "3(9)-y-2(5) = 11<BR>\n" );
document.write( "27-y-10 = 11<BR>\n" );
document.write( "17-y = 11<BR>\n" );
document.write( "y = 6 ...and here's you third mistake. You had y = 14.\r<BR>\n" );
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document.write( "The solution:<BR>\n" );
document.write( "x = 9<BR>\n" );
document.write( "y = 6<BR>\n" );
document.write( "z = 5\r<BR>\n" );
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document.write( "Check:\r<BR>\n" );
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document.write( "1) 3x-y-2z = 11<BR>\n" );
document.write( "3(9)-6-2(5) = 11<BR>\n" );
document.write( "27-6-10 = 11<BR>\n" );
document.write( "27-16 = 11 <BR>\n" );
document.write( "11 = 11 OK here.\r<BR>\n" );
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document.write( "2) x-2y+3z = 12<BR>\n" );
document.write( "9-2(6)+3(5) = 12<BR>\n" );
document.write( "9-12+15 = 12<BR>\n" );
document.write( "24-12 = 12<BR>\n" );
document.write( "12 = 12 OK here too.\r<BR>\n" );
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document.write( "3) x+y-2z = 5<BR>\n" );
document.write( "9+6-2(5) = 5<BR>\n" );
document.write( "9+6-10 = 5<BR>\n" );
document.write( "15-10 = 5<BR>\n" );
document.write( "5 = 5 ...and alright here.<BR>\n" );
document.write( " </SPAN>\n" );
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