document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=865384>Question 865384</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need to solve for both x and y\r<BR>\n" );
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document.write( "x+y=20 x=y-4 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #521665 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=521665\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> x+y=20 ... Start with the first equation.\r<BR>\n" );
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document.write( "y-4+y=20 ... Replace x with y-4 (since x = y-4 is the second equation).\r<BR>\n" );
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document.write( "Now we solve for y\r<BR>\n" );
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document.write( "y-4+y=20\r<BR>\n" );
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document.write( "2y-4=20\r<BR>\n" );
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document.write( "2y=20+4\r<BR>\n" );
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document.write( "2y=24\r<BR>\n" );
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document.write( "y=24/2\r<BR>\n" );
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document.write( "<font color=\"red\">y = 12</font>\r<BR>\n" );
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document.write( "Once we know that <font color=\"red\">y = 12</font>, we plug this into any equation that has x,y in it to solve for x. The easiest to pick on is the one where x is already isolated.\r<BR>\n" );
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document.write( "x = y-4\r<BR>\n" );
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document.write( "x = 12-4 ... replace y with 12 (since we just found that y = 12)\r<BR>\n" );
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document.write( "<font color=\"red\">x = 8</font>\r<BR>\n" );
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document.write( "Final Answer: <font color=\"red\">x = 8, y = 12</font>\r<BR>\n" );
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document.write( "The answer as an ordered pair is <font color=\"red\">(8,12)</font>. Visually, this is where the two lines intersect.<BR>\n" );
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