document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=120624>Question 120624</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 2x+y=9<BR>\n" );
document.write( "-3x+2y=4 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #88524 by </B><A HREF=/tutors/aboutme.mpl?userid=nabla><B>nabla(475)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nabla><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=88524\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Solve the first equation for y:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=-2x%2B9 ALIGN=MIDDLE  ALT=\"y=-2x%2B9\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Substitute this y into the second equation:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-3x%2B2%28-2x%2B9%29=4 ALIGN=MIDDLE  ALT=\"-3x%2B2%28-2x%2B9%29=4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-7x=-14 ALIGN=MIDDLE  ALT=\"-7x=-14\"   DISABLED_style= \"max-width:90%; height:auto;\" > Combine terms on the left, subtract 19 from both sides<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=2 ALIGN=MIDDLE  ALT=\"x=2\"   DISABLED_style= \"max-width:90%; height:auto;\" > Divide both sides by -7.\r<BR>\n" );
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document.write( "Now, substitute this value of x into the first equation where we solved for y in terms of x: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=-2%282%29%2B9=-4%2B9=5 ALIGN=MIDDLE  ALT=\"y=-2%282%29%2B9=-4%2B9=5\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "This gives the solution set S:{2,5}.\r<BR>\n" );
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document.write( "Additionally, we could solve this system through techniques of linear algebra as follows: <BR>\n" );
document.write( "Matrix: <BR>\n" );
document.write( "|2  1  9|<BR>\n" );
document.write( "|-3 2  4|\r<BR>\n" );
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document.write( "(3/2)R1+R2-><BR>\n" );
document.write( "|2  1       9|<BR>\n" );
document.write( "|0  7/2  35/2|\r<BR>\n" );
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document.write( "(1/2)R1-><BR>\n" );
document.write( "|1  1/2   9/2|<BR>\n" );
document.write( "|0  7/2  35/2|\r<BR>\n" );
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document.write( "(2/7)R2-><BR>\n" );
document.write( "|1  1/2   9/2|<BR>\n" );
document.write( "|0  1      5 |\r<BR>\n" );
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document.write( "-1/2R2+R1-><BR>\n" );
document.write( "|1  0      2 |<BR>\n" );
document.write( "|0  1      5 |\r<BR>\n" );
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document.write( "Making S={2,5} the only solution. </SPAN>\n" );
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