document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=177969>Question 177969</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve each system by addition<BR>\n" );
document.write( "x+y=7<BR>\n" );
document.write( "x-y=9 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #132938 by </B><A HREF=/tutors/aboutme.mpl?userid=Mathtut><B>Mathtut(3670)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Mathtut><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=132938\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> addition is really just another name for elimination<BR>\n" );
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document.write( "these two equations are already set up and do not have to be manipulated at all because one of the variables will be eliminated just by adding the equations together.<BR>\n" );
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document.write( "x+y=7....eq 1<BR>\n" );
document.write( "x-y=9....eq 2<BR>\n" );
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document.write( "notice as these are lined up that when we add the two equations together the y terms are eliminated? why? because +y-y=0.  We are left with x+x=7+9<BR>\n" );
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document.write( "2x=16<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28x=8%29 ALIGN=MIDDLE  ALT=\"highlight%28x=8%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "now take x's found value of 8 and plug it into either eq 1 or 2 and solve for y. I chose eq 1<BR>\n" );
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document.write( "8+y=7<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28y=-1%29 ALIGN=MIDDLE  ALT=\"highlight%28y=-1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "so the solution(8,-1) whould work in both equations<BR>\n" );
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document.write( "x+y=7....eq 1--->8+(-1)=7--->7=7....check<BR>\n" );
document.write( "x-y=9....eq 2--->8-(-1)=9--->9=9....check<BR>\n" );
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