document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=749711>Question 749711</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve By Substitution:<BR>\n" );
document.write( "-3x+4y=-18<BR>\n" );
document.write( "x=-2y-4 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #456217 by </B><A HREF=/tutors/aboutme.mpl?userid=lenny460><B>lenny460(1073)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lenny460><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=lenny460><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=456217\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Solve By Substitution:<BR>\n" );
document.write( "-3x + 4y = -18<BR>\n" );
document.write( "x = -2y - 4\r<BR>\n" );
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document.write( "Substitute x = -2y - 4 into the first equation.\r<BR>\n" );
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document.write( "-3x + 4y = -18\r<BR>\n" );
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document.write( "-3(-2y - 4) + 4y = -18\r<BR>\n" );
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document.write( "-3 * -2y = 6y\r<BR>\n" );
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document.write( "-3 * -4 = 12\r<BR>\n" );
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document.write( "We now have:\r<BR>\n" );
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document.write( "6y + 12 + 4y = -18\r<BR>\n" );
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document.write( "Combine like terms:\r<BR>\n" );
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document.write( "6y + 4y = 10y\r<BR>\n" );
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document.write( "10y + 12 = -18\r<BR>\n" );
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document.write( "Subtract 12 from each side of the equation.\r<BR>\n" );
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document.write( "10y + 12 - 12 = -18 - 12\r<BR>\n" );
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document.write( "Combine like terms:\r<BR>\n" );
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document.write( "12 - 12 = 0\r<BR>\n" );
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document.write( "-18 - 12 = -30\r<BR>\n" );
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document.write( "Therefore:\r<BR>\n" );
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document.write( "10y = -30\r<BR>\n" );
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document.write( "Divide each side by 10\r<BR>\n" );
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document.write( "10y/10 = -30/10\r<BR>\n" );
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document.write( "y = -3\r<BR>\n" );
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document.write( "Now substitute y = -3 into the second equation.\r<BR>\n" );
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document.write( "x = -2y - 4\r<BR>\n" );
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document.write( "x = -2(-3) - 4\r<BR>\n" );
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document.write( "-2(-3) = 6\r<BR>\n" );
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document.write( "x = 6 - 4\r<BR>\n" );
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document.write( "6 - 4 = 2\r<BR>\n" );
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document.write( "x = 2\r<BR>\n" );
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document.write( "Answer:\r<BR>\n" );
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document.write( "x = 2 and\r<BR>\n" );
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document.write( "y = -3\r<BR>\n" );
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document.write( "Lennox Obuong<BR>\n" );
document.write( "Algebra Tutor<BR>\n" );
document.write( "Nairobi, Kenya<BR>\n" );
document.write( "Email: obuong3@aol.com </SPAN>\n" );
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