document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=82890>Question 82890</A>: <I><SPAN STYLE=\"word-break: break-all;\"> solve the system of equations by sustitution\r<BR>\n" );
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document.write( "3x+4y=-20<BR>\n" );
document.write( "x+y=-6 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #59468 by </B><A HREF=/tutors/aboutme.mpl?userid=afphrodietic><B>afphrodietic(3)</B></A><img src=\"/images/stars/iconNewId_16x16.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=afphrodietic><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=59468\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let 3x+4y=-20 be the first equation<BR>\n" );
document.write( "and x+y=-6 the second equation.\r<BR>\n" );
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document.write( "then, the second equation becomes x=-6-y.<BR>\n" );
document.write( "plug it in the first equation.\r<BR>\n" );
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document.write( "3(-6-y)+4y=-20<BR>\n" );
document.write( "-18-3y+4y=-20<BR>\n" );
document.write( "-18+y=-20<BR>\n" );
document.write( "y=-20+18<BR>\n" );
document.write( "y=-2\r<BR>\n" );
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document.write( "and\r<BR>\n" );
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document.write( "x+(-2)=-6<BR>\n" );
document.write( "x-2=-6<BR>\n" );
document.write( "x=-6+2<BR>\n" );
document.write( "x=-4\r<BR>\n" );
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document.write( "Then, check:\r<BR>\n" );
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document.write( "3(-4)+4(-2)=-20<BR>\n" );
document.write( "-12+(-8)=-20<BR>\n" );
document.write( "-12-8=-20<BR>\n" );
document.write( "-20=-20 </SPAN>\n" );
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