document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=262455>Question 262455</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am trying to help my niece with her homework and I need step-by-step instructions on how to use substitution to solve a system of equations.<BR>\n" );
document.write( "Example:<BR>\n" );
document.write( "2x + 3y = 5<BR>\n" );
document.write( "4x - 9y = 9\r<BR>\n" );
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document.write( "Thanks for any help that you can share!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #193373 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=193373\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the \"trick\" is to substitute an equivalent value to get an equation with only one variable\r<BR>\n" );
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document.write( "look for a simple ratio between the terms of the SAME variable in the different equations<BR>\n" );
document.write( "___ eg. the x term in the first equation is 2, while the x term in the second equation is 4<BR>\n" );
document.write( "___ a simple ratio of 1:2\r<BR>\n" );
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document.write( "subtracting 3y in the first equation gives ___ 2x = 5 - 3y\r<BR>\n" );
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document.write( "in the second equation, the 4x term can be thought of as 2(2x)\r<BR>\n" );
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document.write( "so substituting the equivalent value of 2x from the first equation gives ___ 2(5 - 3y) - 9y = 9\r<BR>\n" );
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document.write( "distributing the 2 ___ 10 - 6y - 9y = 9 ___ 1 = 15y ___ 1/15 = y\r<BR>\n" );
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document.write( "substituting the value of y into the first equation ___ 2x + 3(1/15) = 5 ___ 2x = 72/15 ___ x = 36/15 = 12/5 </SPAN>\n" );
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