document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=72830>Question 72830</A>: <I><SPAN STYLE=\"word-break: break-all;\"> by using subsitution of linear systems how do you figure out this problem?  \r<BR>\n" );
document.write( "\n" );
document.write( "           x+y=4<BR>\n" );
document.write( "          -5+2y=-6 <BR>\n" );
document.write( "     <BR>\n" );
document.write( "                            PLEASE HELP CUZ IM NOT UNDERSTANING THIS </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #52118 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=52118\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Solve one of the equations for a single variable (I'm going to solve for y on the top). You then plug this y value into any y you see into the 2nd equation<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=4-x ALIGN=MIDDLE  ALT=\"y=4-x\"   DISABLED_style= \"max-width:90%; height:auto;\" >Solve for y<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-5%2B2%284-x%29=-6 ALIGN=MIDDLE  ALT=\"-5%2B2%284-x%29=-6\"   DISABLED_style= \"max-width:90%; height:auto;\" >Now you can solve for x<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-5%2B8-2x=-6 ALIGN=MIDDLE  ALT=\"-5%2B8-2x=-6\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-2x=-9 ALIGN=MIDDLE  ALT=\"-2x=-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=9%2F2 ALIGN=MIDDLE  ALT=\"x=9%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Now plug this into x+y=4<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=9%2F2%2By=4 ALIGN=MIDDLE  ALT=\"9%2F2%2By=4\"   DISABLED_style= \"max-width:90%; height:auto;\" >Solve for y<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=4-9%2F2 ALIGN=MIDDLE  ALT=\"y=4-9%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=%288-9%29%2F2 ALIGN=MIDDLE  ALT=\"y=%288-9%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=-1%2F2 ALIGN=MIDDLE  ALT=\"y=-1%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "So the solution is (9/2,-1/2) or (4.5,-0.5). In a nutshell you are substituting to eliminate one variable. This allows you to work with one variable, since you cannot simultaneously solve for 2 variables. You then take the answer of one and plug it in the other equation. Hope this helps. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );