document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=472863>Question 472863</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Is the line through points P(1, 9) and Q(9, 6) perpendicular to the line through points R(-6, 0) and S(-9, 8)? Explain.\r<BR>\n" );
document.write( "\n" );
document.write( "a. Yes; their slopes have product -1<BR>\n" );
document.write( "b. No; their slopes are not opposite reciprocals.<BR>\n" );
document.write( "c. No; their slopes are not equal<BR>\n" );
document.write( "d. Yes; their slopes are equal </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #324195 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=324195\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Is the line through points P(1, 9) and Q(9, 6) perpendicular to the line through points R(-6, 0) and S(-9, 8)? Explain.\r<BR>\n" );
document.write( "\n" );
document.write( "--------------<BR>\n" );
document.write( "Slope m = diffy/diffx<BR>\n" );
document.write( "The slope of PQ is -3/8<BR>\n" );
document.write( "The slope of RS is 8/-3 = -8/3<BR>\n" );
document.write( "-----------------<BR>\n" );
document.write( "b.<BR>\n" );
document.write( "The lines will intersect, but they're not perpendicular.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );