document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=162132>Question 162132</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can you help me with the following question?\r<BR>\n" );
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document.write( "Solve each system by elimination. Check your answers.  #4<BR>\n" );
document.write( " {a+b+c=-3<BR>\n" );
document.write( " {  3b-c=4<BR>\n" );
document.write( " {2a-b-2c=-5 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #119590 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=119590\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> line the equations up by putting 0 for the missing variables:<BR>\n" );
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document.write( "a + b + c = -3<BR>\n" );
document.write( "0 +3b - c = +4<BR>\n" );
document.write( "2a -b -2c = -5<BR>\n" );
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document.write( "Add equations 1 and 3:<BR>\n" );
document.write( "a + b + c = -3<BR>\n" );
document.write( "2a -b -2c = -5<BR>\n" );
document.write( "------------------addition eliminates b<BR>\n" );
document.write( "3a - c = -8<BR>\n" );
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document.write( "Multiply equation 3 by 3 and and add to equation 2<BR>\n" );
document.write( "0 +3b - c = +4<BR>\n" );
document.write( "6a-3b -6c = -15<BR>\n" );
document.write( "-------------------addition eliminates b again<BR>\n" );
document.write( "6a - 7c = -11<BR>\n" );
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document.write( "We have two 2 unknown equations now<BR>\n" );
document.write( "3a -  c = - 8<BR>\n" );
document.write( "6a - 7c = -11<BR>\n" );
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document.write( "Multiply the 1st equation by 2, subtract  the 2nd equation:<BR>\n" );
document.write( "6a - 2c = -16<BR>\n" );
document.write( "6a - 7c = -11<BR>\n" );
document.write( "-----------------subtraction eliminates a, find c<BR>\n" );
document.write( "0a + 5c = -5<BR>\n" );
document.write( "c = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-5%29%2F5 ALIGN=MIDDLE  ALT=\"%28-5%29%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "c = -1<BR>\n" );
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document.write( "Use the 1st two unknown equation to find a<BR>\n" );
document.write( "3a -  c = - 8<BR>\n" );
document.write( "3a - (-1) = -8<BR>\n" );
document.write( "3a + 1 = -8<BR>\n" );
document.write( "3a = -8 - 1<BR>\n" );
document.write( "3a = -9<BR>\n" );
document.write( "a = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-9%29%2F3 ALIGN=MIDDLE  ALT=\"%28-9%29%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "a = -3<BR>\n" );
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document.write( "We can find b using the 2nd original equation:<BR>\n" );
document.write( "3b - c = 4<BR>\n" );
document.write( "3b -(-1) = 4<BR>\n" );
document.write( "3b + 1 = 4<BR>\n" );
document.write( "3b = 4 - 1<BR>\n" );
document.write( "3b = 3<BR>\n" );
document.write( "b = +1<BR>\n" );
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document.write( "Check solutions in the original 1st equation<BR>\n" );
document.write( "a + b + c = -3<BR>\n" );
document.write( "-3 + 1 - 1 = -3<BR>\n" );
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document.write( "Was all this understandable, any questions? </SPAN>\n" );
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