document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=347200>Question 347200</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve the system of equations\r<BR>\n" );
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document.write( "3x + y = 1<BR>\n" );
document.write( "-x + 2y = 9\r<BR>\n" );
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document.write( "The answer to this problem is   a.(1, 4) or   b.(-1, 4)\r<BR>\n" );
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document.write( "Some say a some say b. Can someone tell me which is the correct answer and why? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #248268 by </B><A HREF=/tutors/aboutme.mpl?userid=Fombitz><B>Fombitz(32388)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Fombitz><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=Fombitz><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=248268\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Some say a some say b.<BR>\n" );
document.write( "Are you taking a poll? <BR>\n" );
document.write( "There is only 1 right answer.<BR>\n" );
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document.write( "You can do it two ways. <BR>\n" );
document.write( "Plug the values in and see which one satisfies the equation. <BR>\n" );
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document.write( "Although that works, it won't help you next time you don't have an answer to choose from.<BR>\n" );
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document.write( "You can solve by elimination or substitution.<BR>\n" );
document.write( "Substitution: Use 1 equation to solve for 1 variable then substitute for that variable in the second equation.<BR>\n" );
document.write( "1.<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3x+%2B+y+=+1 ALIGN=MIDDLE  ALT=\"3x+%2B+y+=+1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "2.<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-x+%2B+2y+=+9 ALIGN=MIDDLE  ALT=\"-x+%2B+2y+=+9\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "From eq. 2,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=2y-9 ALIGN=MIDDLE  ALT=\"x=2y-9\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Substitute into eq. 1,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3%282y-9%29%2By=1 ALIGN=MIDDLE  ALT=\"3%282y-9%29%2By=1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6y-27%2By=1 ALIGN=MIDDLE  ALT=\"6y-27%2By=1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7y=28 ALIGN=MIDDLE  ALT=\"7y=28\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28y=4%29 ALIGN=MIDDLE  ALT=\"highlight%28y=4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Then from eq. 2,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=2%284%29-9 ALIGN=MIDDLE  ALT=\"x=2%284%29-9\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=8-9 ALIGN=MIDDLE  ALT=\"x=8-9\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28x=-1%29 ALIGN=MIDDLE  ALT=\"highlight%28x=-1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "The other method is elimination.<BR>\n" );
document.write( "Manipulate the equations to eliminate one of the variables.<BR>\n" );
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document.write( "1.<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3x+%2B+y+=+1 ALIGN=MIDDLE  ALT=\"3x+%2B+y+=+1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "2.<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-x+%2B+2y+=+9 ALIGN=MIDDLE  ALT=\"-x+%2B+2y+=+9\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Multiply eq. 2 by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3 ALIGN=MIDDLE  ALT=\"3\"   DISABLED_style= \"max-width:90%; height:auto;\" > and add the equations together.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3x%2By-3x%2B6y=1%2B27 ALIGN=MIDDLE  ALT=\"3x%2By-3x%2B6y=1%2B27\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7y=28 ALIGN=MIDDLE  ALT=\"7y=28\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=4 ALIGN=MIDDLE  ALT=\"y=4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Then use either equation to solve for <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x ALIGN=MIDDLE  ALT=\"x\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
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document.write( "Isn't that better than guessing? </SPAN>\n" );
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