document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1155559>Question 1155559</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solving:\r<BR>\n" );
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document.write( "      5 x-3y = 18 <BR>\n" );
document.write( "      -3 x-3y = -12 \r<BR>\n" );
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document.write( "Using Substitution Method.\r<BR>\n" );
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document.write( "Expressing x as a function of y (from the first equation) x = (18  +3y)/5\r<BR>\n" );
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document.write( "Substituting this expression into the second equation:\r<BR>\n" );
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document.write( "	-3 (18 -3y)/5-3y = -12 \r<BR>\n" );
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document.write( "Why is this not -3(18+3y)/5-3y = -12 ?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #778171 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52787)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=778171\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .\r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;I will do it using substitution method, &nbsp;but I will use a &nbsp;TRICK &nbsp;to avoid using fractions on the way.\r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Watch my steps carefully.\r<BR>\n" );
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document.write( "Express 3y from the first equation  3y = 5x - 18  and then substitute this expression into the second equation, replacing 3y there\r\n" );
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document.write( "    -3x - (5x-18) = -12.\r\n" );
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document.write( "Now simplify and find x\r\n" );
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document.write( "    - 3x - 5x + 18 = -12\r\n" );
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document.write( "    - 8x           = - 12 - 18\r\n" );
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document.write( "     -8x           = - 30\r\n" );
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document.write( "       x = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-30%29%2F%28-8%29 ALIGN=MIDDLE  ALT=\"%28-30%29%2F%28-8%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=30%2F8 ALIGN=MIDDLE  ALT=\"30%2F8\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 3.75.\r\n" );
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document.write( "Now you substitute this found value of x into either of the two original equations and find y.\r\n" );
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document.write( "--------------\r<BR>\n" );
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document.write( "Learn this trick from my post.\r<BR>\n" );
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document.write( "There is a lesson in this site, demonstrating this trick in work\r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;- <A  rel=nofollow HREF=https://www.algebra.com/algebra/homework/coordinate/lessons/Useful-tricks-when-solving-systems-of-2-eqns-in-2-unknowns-by-the-Subst-method.lesson>Useful tricks when solving systems of 2 equations in 2 unknowns by the Substitution method</A> \r<BR>\n" );
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