document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=748164>Question 748164</A>: <I><SPAN STYLE=\"word-break: break-all;\"> is 9x+3y=12; 27x+9y=40 parallel, perpendicular, or neither? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #455361 by </B><A HREF=/tutors/aboutme.mpl?userid=tommyt3rd><B>tommyt3rd(5050)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=tommyt3rd><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=tommyt3rd><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=455361\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> We know that two lines are parallel if they have the same slope (and they are distinct). When the lines are in general form we'll use the formula m=-B/A to find their slopes with\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%0D%0AAx%2BBy=C%0D%0A ALIGN=MIDDLE  ALT=\"%0D%0AAx%2BBy=C%0D%0A\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%0D%0A9x%2B3y=12%0D%0A ALIGN=MIDDLE  ALT=\"%0D%0A9x%2B3y=12%0D%0A\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%0D%0A27x%2B9y=40%0D%0A ALIGN=MIDDLE  ALT=\"%0D%0A27x%2B9y=40%0D%0A\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "first line: m=-3/9=-1/3\r<BR>\n" );
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document.write( "second line: m=-9/27=-1/3\r<BR>\n" );
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document.write( "these lines have the same slope and since we know that they are not the same line because\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%0D%0A%0D%0AA%5B1%5D%2FA%5B2%5D+%3C%3E+C%5B1%5D%2FC%5B2%5D%0D%0A ALIGN=MIDDLE  ALT=\"%0D%0A%0D%0AA%5B1%5D%2FA%5B2%5D+%3C%3E+C%5B1%5D%2FC%5B2%5D%0D%0A\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "they must be parallel\r<BR>\n" );
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document.write( ":) </SPAN>\n" );
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