document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=122293>Question 122293</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve the system by addition \r<BR>\n" );
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document.write( "4x+8y=-1<BR>\n" );
document.write( "8x-4y=-7 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #89787 by </B><A HREF=/tutors/aboutme.mpl?userid=tutor_paul><B>tutor_paul(519)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=tutor_paul><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=tutor_paul><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=89787\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 4x+8y=-1<BR>\n" );
document.write( "8x-4y=-7<BR>\n" );
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document.write( "Multiply the bottom equation by 2. The reason I picked 2 was because that give me a -8y term, which, when added to the top equation eliminates the y term:<BR>\n" );
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document.write( "4x+8y=-1<BR>\n" );
document.write( "16x-8y=-14\r<BR>\n" );
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document.write( "Add them and you get:<BR>\n" );
document.write( "20x=-15<BR>\n" );
document.write( "x=-15/20<BR>\n" );
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document.write( "Take the original equations again, and this time multiply the top by -2. This will eliminate the x term when I add them. You get:<BR>\n" );
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document.write( "-8x-16y=2<BR>\n" );
document.write( "8x-4y=-7\r<BR>\n" );
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document.write( "Add them and you get:<BR>\n" );
document.write( "-20y=-5<BR>\n" );
document.write( "y=5/20<BR>\n" );
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document.write( "Good Luck,<BR>\n" );
document.write( "tutor_paul@yahoo.com<BR>\n" );
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