document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=394023>Question 394023</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Using Substitution, solve.<BR>\n" );
document.write( "x+y=4<BR>\n" );
document.write( "y=2x+1 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #279541 by </B><A HREF=/tutors/aboutme.mpl?userid=pie90010><B>pie90010(44)</B></A><img src=\"/images/stars/stars-07.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=pie90010><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=279541\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> So it depends which variable you want to use, ill use x in this case\r<BR>\n" );
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document.write( "take the equation x+y=4 and isolate the x so its<BR>\n" );
document.write( "x = (4 - y)\r<BR>\n" );
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document.write( "then in the other equation, replace x with (4-y)\r<BR>\n" );
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document.write( "y = 2(4 - y) + 1\r<BR>\n" );
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document.write( "Now you have only one variable :D\r<BR>\n" );
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document.write( "y = 8 - 2y + 1\r<BR>\n" );
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document.write( "combine like terms, yada yada\r<BR>\n" );
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document.write( "3y = 9<BR>\n" );
document.write( "y = 3\r<BR>\n" );
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document.write( "Now just plug the number in to the original equation to get X \r<BR>\n" );
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document.write( "x + 3 = 4<BR>\n" );
document.write( "X = 1\r<BR>\n" );
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document.write( "the answer would be (1,3)<BR>\n" );
document.write( " </SPAN>\n" );
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