document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=3869>Question 3869</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Sorry Jon!\r<BR>\n" );
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document.write( "It is <BR>\n" );
document.write( "x + 7y = -39<BR>\n" );
document.write( "-3x - 2y = 22\r<BR>\n" );
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document.write( "Substitution method ,I can't get it to work out. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #1709 by </B><A HREF=/tutors/aboutme.mpl?userid=longjonsilver><B>longjonsilver(2297)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=longjonsilver><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=longjonsilver><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=1709\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let 2 eqns be eqn1 and eqn2, respectively.\r<BR>\n" );
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document.write( "in eqn1, x = -39 - 7y. So put this (ie substitute it) into the second eqn, which becomes:\r<BR>\n" );
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document.write( "-3(-39-7y) - 2y = 22 --> expand the bracket and simply it all:<BR>\n" );
document.write( "117+21y - 2y = 22<BR>\n" );
document.write( "19y = 22-117<BR>\n" );
document.write( "19y = -95<BR>\n" );
document.write( "y = -95/19<BR>\n" );
document.write( "y = -5.\r<BR>\n" );
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document.write( "So now put this into either eqn1 or eqn2..pick the easiest looking one!... eqn2\r<BR>\n" );
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document.write( "This becomes -3x -2(-5) = 22<BR>\n" );
document.write( "-3x + 10 = 22<BR>\n" );
document.write( "-3x = 22-10<BR>\n" );
document.write( "-3x = 12<BR>\n" );
document.write( "x = -12/3<BR>\n" );
document.write( "x = -4\r<BR>\n" );
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document.write( "Now but both answers into the other eqn and see if you do get -39. If you do, you KNOW the answer is correct!\r<BR>\n" );
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document.write( "-4 + 7(-5)<BR>\n" );
document.write( "-4 - 35<BR>\n" );
document.write( "-39 --> CORRECT!!\r<BR>\n" );
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document.write( "jon.<BR>\n" );
document.write( " </SPAN>\n" );
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