document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=428696>Question 428696</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I know how to solve for X and Y in linear systems of equations using SUBSTITUTION. My teacher wants us to use ELIMINATION.  The tool on this site asks me to check \"Elimination or Substitution\", but even when I ask it to use elimination--it solves my problem by substitution!  I don't get the difference!!  ex problem:\r<BR>\n" );
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document.write( "7x + 4y = 2<BR>\n" );
document.write( "7x + 2y = 8<BR>\n" );
document.write( " My answer is x=2  y=-3   Which I got by isolating 7x in each equation, then setting 2 equations equal to each other   2-4y = 8-2y </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #297918 by </B><A HREF=/tutors/aboutme.mpl?userid=htmentor><B>htmentor(1343)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=htmentor><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=htmentor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=297918\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 7x + 4y = 2<BR>\n" );
document.write( "7x + 2y = 8<BR>\n" );
document.write( "To solve by elimination, perform addition or subtraction of the two equations to eliminate one of the variables.  In this case, subtract equation (2) from equation (1):<BR>\n" );
document.write( "2y = -6 -> y = -3<BR>\n" );
document.write( "To get x, substitute into one of the equations:<BR>\n" );
document.write( "7x + 4(-3) = 2 -> 7x = 12 + 2 -> x = 2<BR>\n" );
document.write( "Ans: x=2, y=-3 </SPAN>\n" );
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