document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=221134>Question 221134</A>: <I><SPAN STYLE=\"word-break: break-all;\"> solve by subsititution method 9m+n=77 m-3n=21 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #165975 by </B><A HREF=/tutors/aboutme.mpl?userid=MathTherapy><B>MathTherapy(10555)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathTherapy><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=MathTherapy><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=165975\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> solve by subsititution method 9m+n=77 m-3n=21\r<BR>\n" );
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document.write( "9m + n = 77 ------ (i)\r<BR>\n" );
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document.write( "m - 3n = 21 ------(ii)\r<BR>\n" );
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document.write( "m  =  21 + 3n ----- Solving for m in eq (ii)\r<BR>\n" );
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document.write( "9(21 + 3n) + n = 77 ------ Substituting 21 + 3n for m in eq (i)\r<BR>\n" );
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document.write( "189 + 27n + n = 77\r<BR>\n" );
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document.write( "28n = - 112\r<BR>\n" );
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document.write( "n = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-112%2F28 ALIGN=MIDDLE  ALT=\"-112%2F28\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight_green%28-4%29 ALIGN=MIDDLE  ALT=\"highlight_green%28-4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "m - 3(-4) = 21 ----- Substituting - 4 for n in eq (ii)\r<BR>\n" );
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document.write( "m + 12  =  21\r<BR>\n" );
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document.write( "m  =  21 - 12 = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight_green%289%29 ALIGN=MIDDLE  ALT=\"highlight_green%289%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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