document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=452069>Question 452069</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve with the substitution method.<BR>\n" );
document.write( "7m + n=12<BR>\n" );
document.write( "m-8n = 75<BR>\n" );
document.write( "What is the ordered pair? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #310775 by </B><A HREF=/tutors/aboutme.mpl?userid=AHBK><B>AHBK(13)</B></A><img src=\"/images/stars/stars-06.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=AHBK><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=310775\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> ok we have 7m+n=12 and m-8n=75 .<BR>\n" );
document.write( "you want to solve it by substitution method so here we go...<BR>\n" );
document.write( "we have m-8n=75,<BR>\n" );
document.write( "so m=8n+75,<BR>\n" );
document.write( "then we substitute the value of m in the equation (7m+n=12)<BR>\n" );
document.write( "we get : 7(8n+75)+n=12. we expand.<BR>\n" );
document.write( "we get : 56n+525+n=12,<BR>\n" );
document.write( "so , 57n+525=12<BR>\n" );
document.write( "57n=12-525, 57n= -513,<BR>\n" );
document.write( "so n=-(513/57) , then n= -9<BR>\n" );
document.write( "then substitute the value of n in any equation you want lets go with (7m+n=12) not necessarily this equation you can pick the other one you will get the same solution.<BR>\n" );
document.write( "7m+n=12, 7m+(-9)=12 , 7m-9=12, 7m=12+9 ,<BR>\n" );
document.write( "so 7m=21,<BR>\n" );
document.write( "then m= 21/7<BR>\n" );
document.write( "m=3<BR>\n" );
document.write( "and solution is m=3 and n= -9  </SPAN>\n" );
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