document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=116221>Question 116221</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help.\r<BR>\n" );
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document.write( "Solve the system by addition. <BR>\n" );
document.write( "5x-3y=13<BR>\n" );
document.write( "4x-3y=11 <BR>\n" );
document.write( "Thanks<BR>\n" );
document.write( "JMS<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 #84559 by </B><A HREF=/tutors/aboutme.mpl?userid=bucky><B>bucky(2189)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=bucky><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=84559\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> To solve by addition, one of the equations must have a term that is equal to the same term in<BR>\n" );
document.write( "the other equation, but these terms have opposite signs.<BR>\n" );
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document.write( "You are given the two equations:<BR>\n" );
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document.write( "+5x-3y=+13<BR>\n" );
document.write( "+4x-3y=+11 <BR>\n" );
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document.write( "Notice that the term 3y appears in both equations, but they have the same sign. How about <BR>\n" );
document.write( "if we multiply the bottom equation (all terms on both sides) by -1. When we do that the<BR>\n" );
document.write( "pair of equations becomes:<BR>\n" );
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document.write( "+5x-3y=+13<BR>\n" );
document.write( "-4x+3y=-11 <BR>\n" );
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document.write( "Now you can add the two equations in vertical columns. When you do the -3y and the +3y <BR>\n" );
document.write( "cancel each other out and the addition results in:<BR>\n" );
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document.write( "x = 2<BR>\n" );
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document.write( "Substitute that value of x into either of the original problems and solve for y. Let's make<BR>\n" );
document.write( "that substitution into the first equation. Start with:<BR>\n" );
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document.write( "+5x - 3y = 13<BR>\n" );
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document.write( "Substitute -2 for x to get:<BR>\n" );
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document.write( "5(2) - 3y = 13<BR>\n" );
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document.write( "Multiply out the first term:<BR>\n" );
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document.write( "10 - 3y = 13<BR>\n" );
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document.write( "subtract 10 from both sides of this equation:<BR>\n" );
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document.write( "-3y = +3<BR>\n" );
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document.write( "Divide both sides by -3 to solve for y and you get:<BR>\n" );
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document.write( "y = 3/-3 = -1<BR>\n" );
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document.write( "In summary the answer to this problem is x = 2 and y = -1.<BR>\n" );
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document.write( "Hope this helps you to understand the problem and how to solve it.<BR>\n" );
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