document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=507468>Question 507468</A>: <I><SPAN STYLE=\"word-break: break-all;\"> by substitution:<BR>\n" );
document.write( "1. y=3x<BR>\n" );
document.write( "y-x=30\r<BR>\n" );
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document.write( "2. x=y<BR>\n" );
document.write( "2x+2y=120\r<BR>\n" );
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document.write( "Please help meeee. :)\r<BR>\n" );
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document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #340532 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=340532\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> y-x=30\r<BR>\n" );
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document.write( "3x-x=30 ... plug in y = 3x (ie replace y with 3x)\r<BR>\n" );
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document.write( "2x=30\r<BR>\n" );
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document.write( "x=30/2\r<BR>\n" );
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document.write( "x=15\r<BR>\n" );
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document.write( "----\r<BR>\n" );
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document.write( "y = 3x\r<BR>\n" );
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document.write( "y = 3(15)\r<BR>\n" );
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document.write( "y = 45\r<BR>\n" );
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document.write( "So x = 15 and y = 45\r<BR>\n" );
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document.write( "# 2\r<BR>\n" );
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document.write( "2x + 2y =120 \r<BR>\n" );
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document.write( "2y + 2y =120 ... plug in x = y (ie replace x with y)\r<BR>\n" );
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document.write( "4y =120 \r<BR>\n" );
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document.write( "y =120/4\r<BR>\n" );
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document.write( "y =30\r<BR>\n" );
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document.write( "So x = 30 and y = 30 </SPAN>\n" );
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