document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=65799>Question 65799</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/093979862x/algebrahomeworkh>An Incremental Development</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> solve\r<BR>\n" );
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document.write( "2x - 3y - 3z = 2<BR>\n" );
document.write( "x + 5y + 2z = -3<BR>\n" );
document.write( "x + 2y = 0\r<BR>\n" );
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document.write( "thank you </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #46571 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=46571\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> solve\r<BR>\n" );
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document.write( "Eq 1: 2x - 3y - 3z = 2<BR>\n" );
document.write( "Eq 2: x + 5y + 2z = -3<BR>\n" );
document.write( "Eq 3: x + 2y = 0<BR>\n" );
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document.write( "It's quite easy to get this to a \"two equation two unknown\" situation using Eq 3.<BR>\n" );
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document.write( "x + 2y = 0<BR>\n" );
document.write( "x = -2y<BR>\n" );
document.write( "Substitute -2y for x in eq 1 and 2<BR>\n" );
document.write( "2(-2y) - 3y - 3z = 2   <BR>\n" );
document.write( "-4y - 3y - 3z = 2      <BR>\n" );
document.write( "-7y - 3z = 2<BR>\n" );
document.write( "and<BR>\n" );
document.write( "-2y + 5y + 2z = -3<BR>\n" );
document.write( "3y + 2z = -3<BR>\n" );
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document.write( "Mult -7y + 3z = 2 by 2 and 3y + 2z =-3 by 3 and you have:<BR>\n" );
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document.write( "-14y - 6z = 4<BR>\n" );
document.write( " 9y + 6z = -9<BR>\n" );
document.write( "----------------adding eliminates z, solve for y<BR>\n" );
document.write( "-5y + 0 = -5<BR>\n" );
document.write( "y = -5/-5<BR>\n" );
document.write( "y = +1 <BR>\n" );
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document.write( "Use equation 3 to find x<BR>\n" );
document.write( "x + 2y + 0<BR>\n" );
document.write( "x + 2(1) = 0<BR>\n" );
document.write( "x = -2<BR>\n" );
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document.write( "Substitute for x and in equation 1 and find z<BR>\n" );
document.write( "2x - 3y - 3z = 2<BR>\n" );
document.write( "2(-2) - 3(1)- 3z = 2<BR>\n" );
document.write( "-4 - 3(1) - 3z = 2<BR>\n" );
document.write( "-7 - 3z = 2<BR>\n" );
document.write( "-3z = 2+7<BR>\n" );
document.write( "z = 9/-3<BR>\n" );
document.write( "z = -3<BR>\n" );
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document.write( "Check our solutions in the 2nd equation:<BR>\n" );
document.write( "x + 5y + 2z = -3<BR>\n" );
document.write( "-2 + 5(1) + 2(-3) = -3<BR>\n" );
document.write( "-2 + 5 - 6 = -3 proves our solutions  <BR>\n" );
document.write( " </SPAN>\n" );
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