document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=449380>Question 449380</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need help with this question please:\r<BR>\n" );
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document.write( "Solve the system of equations \r<BR>\n" );
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document.write( "x + y =  5  <BR>\n" );
document.write( "x - y =  -9      </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #309125 by </B><A HREF=/tutors/aboutme.mpl?userid=Math_Teacher_37><B>Math_Teacher_37(4)</B></A><img src=\"/images/stars/iconNewId_16x16.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Math_Teacher_37><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=309125\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> We are trying to solve the following system of equations:\r<BR>\n" );
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document.write( "x + y = 5<BR>\n" );
document.write( "x - y = -9\r<BR>\n" );
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document.write( "Notice that the \"y\" terms are opposite in sign so we can simply add the equations together, like this:\r<BR>\n" );
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document.write( "2x + 0y = -4\r<BR>\n" );
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document.write( "2x = -4\r<BR>\n" );
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document.write( "Divide both sides by 2:  x = -4/2 = -2\r<BR>\n" );
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document.write( "Now, x = -2 so substitute into either equation. Since the first equation involves addition and it looks easier, let's go with this one. We have:\r<BR>\n" );
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document.write( "x + y = 5\r<BR>\n" );
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document.write( "-2 + y = 5\r<BR>\n" );
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document.write( "Add 2 to both sides:\r<BR>\n" );
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document.write( "-2 + 2 + y = 5 + 2\r<BR>\n" );
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document.write( "y = 7\r<BR>\n" );
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document.write( "The solution is: (-2, 7)\r<BR>\n" );
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document.write( " </SPAN>\n" );
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