document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=256201>Question 256201</A>: <I><SPAN STYLE=\"word-break: break-all;\"> how can I tell if two lines are perpendicular?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #188367 by </B><A HREF=/tutors/aboutme.mpl?userid=nerdybill><B>nerdybill(7384)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nerdybill><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=nerdybill><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=188367\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 1. Find the slope of each line<BR>\n" );
document.write( "2. Multiply the two slopes together<BR>\n" );
document.write( "3. If they equal -1, they are perpendicular<BR>\n" );
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document.write( "That is, two lines are perpendicular if their slopes are \"negative reciprocal\". </SPAN>\n" );
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