document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=76478>Question 76478</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve the system by substitution.<BR>\n" );
document.write( "3x-y=-7<BR>\n" );
document.write( "x+y=-9 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #54854 by </B><A HREF=/tutors/aboutme.mpl?userid=chitra><B>chitra(359)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=chitra><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=54854\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The given system of equations are:  \r<BR>\n" );
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document.write( "3x - y = -7     --------------(1)\r<BR>\n" );
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document.write( "x + y = -9      --------------(2)\r<BR>\n" );
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document.write( "EQN (2) can be written as: y = -9 - x  substituting this is EQN (1), we get:  \r<BR>\n" );
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document.write( "3x - (-9 - x) = -7 \r<BR>\n" );
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document.write( "3x + 9 + x = -7 \r<BR>\n" );
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document.write( "4x = - 7 - 9 \r<BR>\n" );
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document.write( "4x = - 16 \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+-+16%2F4 ALIGN=MIDDLE  ALT=\"x+=+-+16%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" > \r<BR>\n" );
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document.write( "==> x = - 4 \r<BR>\n" );
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document.write( "Substituting this in EQN(1) \r<BR>\n" );
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document.write( "3(-4) - y = -7 \r<BR>\n" );
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document.write( "==> -12 - y = -7 \r<BR>\n" );
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document.write( "==> -y = -7 + 12 \r<BR>\n" );
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document.write( "==> - y = 5 \r<BR>\n" );
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document.write( "==> y = -5 \r<BR>\n" );
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document.write( "Hence, the solutions of the given set of equations are given by: \r<BR>\n" );
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document.write( "x = -4 and y = -5 are the solutions. </SPAN>\n" );
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