document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=572586>Question 572586</A>: <I><SPAN STYLE=\"word-break: break-all;\"> solve by substitution method <BR>\n" );
document.write( "5x+2y=-7<BR>\n" );
document.write( "7x+3y=13<BR>\n" );
document.write( "I am having an extremly hard time figuring this out PLEASE help </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #368454 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=368454\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> solve by substitution method <BR>\n" );
document.write( "5x+2y=-7<BR>\n" );
document.write( "7x+3y=13<BR>\n" );
document.write( "----------<BR>\n" );
document.write( "The usual approach is to solve for either x or y in 1 of the eqns.<BR>\n" );
document.write( "----<BR>\n" );
document.write( "5x+2y=-7<BR>\n" );
document.write( "2y = -5x - 7<BR>\n" );
document.write( "y = -5x/2 - 7/2<BR>\n" );
document.write( "----<BR>\n" );
document.write( "Sub for y in the other eqn<BR>\n" );
document.write( "7x+3y=13<BR>\n" );
document.write( "7x + 3(-5x/2 - 7/2) = 13<BR>\n" );
document.write( "7x - 15x/2 - 21/2 = 13<BR>\n" );
document.write( "-x/2 = 47/2<BR>\n" );
document.write( "x = -47<BR>\n" );
document.write( "-------<BR>\n" );
document.write( "y = -5x/2 - 7/2<BR>\n" );
document.write( "y = 235/2 - 7/2<BR>\n" );
document.write( "y = 114<BR>\n" );
document.write( "======================<BR>\n" );
document.write( "A different method:<BR>\n" );
document.write( "5x+2y=-7<BR>\n" );
document.write( "7x+3y=13<BR>\n" );
document.write( "----<BR>\n" );
document.write( "15x + 6y = -21<BR>\n" );
document.write( "14x + 6y = 26<BR>\n" );
document.write( "Solve for 6y, then sub.  You avoid fractions that way.<BR>\n" );
document.write( "15x + 6y = -21<BR>\n" );
document.write( "--> 6y = -15x - 21<BR>\n" );
document.write( "--------------<BR>\n" );
document.write( "21x + 6y = 39<BR>\n" );
document.write( "14x + (-15x - 21) = 26<BR>\n" );
document.write( "etc, same answer<BR>\n" );
document.write( " </SPAN>\n" );
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