document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=335640>Question 335640</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me understand how to solve these equations by the addition method.\r<BR>\n" );
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document.write( "Many thanks.\r<BR>\n" );
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document.write( "2x = 2-y<BR>\n" );
document.write( "3x + y = -1 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #240677 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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/cgi-bin/show-face.mpl?user=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=240677\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 2x = 2 - y<BR>\n" );
document.write( "3x + y = -1<BR>\n" );
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document.write( "We want both equation in the standard form (like the 2nd equation)<BR>\n" );
document.write( "Put the 1st equation in the standard form<BR>\n" );
document.write( "2x = 2 - y<BR>\n" );
document.write( "add y to both sides and you have<BR>\n" );
document.write( "2x + y = 2; the standard form<BR>\n" );
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document.write( "2x + y = 2<BR>\n" );
document.write( "3x + y = -1<BR>\n" );
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document.write( "multiply the 1st equation by -1, then we can use the addition method<BR>\n" );
document.write( "-2x - y = -2<BR>\n" );
document.write( "+3x + y = -1<BR>\n" );
document.write( "------------------addition eliminates y, find x<BR>\n" );
document.write( "x = -3<BR>\n" );
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document.write( "Use the original 2nd equation to find y, <BR>\n" );
document.write( "3x + y = -1<BR>\n" );
document.write( "Replace x with - 3<BR>\n" );
document.write( "3(-3) + y = -1<BR>\n" );
document.write( "-9 + y = -1<BR>\n" );
document.write( "add 9 to both sides<BR>\n" );
document.write( "y = -1 + 9<BR>\n" );
document.write( "y = 8<BR>\n" );
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document.write( "Check our solutions in the original 1st equation<BR>\n" );
document.write( "2x = 2 - y<BR>\n" );
document.write( "Replace x with -3 and y with 8<BR>\n" );
document.write( "2(-3) = 2 - 8<BR>\n" );
document.write( "-6 = -6, equality confirms our solution of x=-3, y=8<BR>\n" );
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document.write( "Did this help you understand this method?? </SPAN>\n" );
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