document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=911299>Question 911299</A>: <I><SPAN STYLE=\"word-break: break-all;\"> substitution to solve the system.<BR>\n" );
document.write( "x-4y=4\r<BR>\n" );
document.write( "\n" );
document.write( "-x+4y=-4 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #553005 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=553005\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> From eq. 1,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=4y%2B4 ALIGN=MIDDLE  ALT=\"x=4y%2B4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Substituting,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-4y-4%2B4y=-4 ALIGN=MIDDLE  ALT=\"-4y-4%2B4y=-4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-4=-4 ALIGN=MIDDLE  ALT=\"-4=-4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "True for all x.<BR>\n" );
document.write( "This is a dependent system. <BR>\n" );
document.write( "If you multiply equation 1 by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-1 ALIGN=MIDDLE  ALT=\"-1\"   DISABLED_style= \"max-width:90%; height:auto;\" > you get equation 2.<BR>\n" );
document.write( "Any solution of equation 1 is a solution of equation 2, infinitely many solutions. </SPAN>\n" );
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