document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=741007>Question 741007</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Using substitution to eliminate one of the variables. Show your work\r<BR>\n" );
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document.write( "x+y=7<BR>\n" );
document.write( "2x+3y=21 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #451812 by </B><A HREF=/tutors/aboutme.mpl?userid=TutorBecky><B>TutorBecky(6)</B></A><img src=\"/images/stars/stars-05.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=TutorBecky><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=451812\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> x+y=7<BR>\n" );
document.write( "2x+3y=21\r<BR>\n" );
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document.write( "Work::\r<BR>\n" );
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document.write( " x + y = 7<BR>\n" );
document.write( "-x     -x<BR>\n" );
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document.write( "y = -1x +7 :::: Just so you don't get confused x is the same as 1x \r<BR>\n" );
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document.write( "Plug the equation into the other for y\r<BR>\n" );
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document.write( "2x + 3 (1x +7 ) = 21 Distribute 3*1x+3*7<BR>\n" );
document.write( "2x + 3x +21 = 21 Combine the same variables : 2x+3x<BR>\n" );
document.write( "5x + 21 = 21 <BR>\n" );
document.write( "   - 21  -21 Subtract 21 on both sides<BR>\n" );
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document.write( "5x =0   Divide by 5 on both sides<BR>\n" );
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document.write( "5   5<BR>\n" );
document.write( "x = 0\r<BR>\n" );
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document.write( "Now to get y \r<BR>\n" );
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document.write( "x + y = 7<BR>\n" );
document.write( "0 + y = 7<BR>\n" );
document.write( "y =7\r<BR>\n" );
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document.write( "Now to check if your right;; Plug in your varibles<BR>\n" );
document.write( "x+y=7<BR>\n" );
document.write( "0+7= 7 <BR>\n" );
document.write( "7 = 7 Check!<BR>\n" );
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document.write( "2(0) + 3 (7) = 21<BR>\n" );
document.write( "0 +21 = 21<BR>\n" );
document.write( "21=21 Check!\r<BR>\n" );
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document.write( "Hope i helped\r<BR>\n" );
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document.write( " </SPAN>\n" );
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