document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=515614>Question 515614</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am working on solving the systems of equations by elimination method.<BR>\n" );
document.write( "{-x+18y=20 and x+18y=25}.  Once these two equations are added together, I come up with 36y=45.  The next step is to solve for y by dividing 36y=45.  My answer is y=5/4.  So far, so good.  \r<BR>\n" );
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document.write( "However, I am having trouble finding x. I rewrite the above equations and substitute 5/4 in the first equation, -x+18y=20.  I substitute 5/4 for y and the answer is x-5/2.  I need to know \"how\" that answer is worked out.\r<BR>\n" );
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document.write( "Thanks.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #344103 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=344103\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  I continue \r<BR>\n" );
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document.write( "x+18y= 25\r<BR>\n" );
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document.write( "x+18*5/4 = 25\r<BR>\n" );
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document.write( "LCD = 4<BR>\n" );
document.write( "multiply by 4\r<BR>\n" );
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document.write( "4x+90=100<BR>\n" );
document.write( "4x=10<BR>\n" );
document.write( "x=10/4<BR>\n" );
document.write( "x=5/2 </SPAN>\n" );
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