document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=628278>Question 628278</A>: <I><SPAN STYLE=\"word-break: break-all;\"> how to decide whether the lines given are parallel, perpendicular or neither\r<BR>\n" );
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document.write( "The line through (7,1) and (9,3)<BR>\n" );
document.write( "The line through (6,4) and (4,6)<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #395513 by </B><A HREF=/tutors/aboutme.mpl?userid=reviewermath><B>reviewermath(1029)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=reviewermath><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=reviewermath><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=395513\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The slope of the line joining (7,1) and (9,3) is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%283-1%29%2F%289-7%29+=+1 ALIGN=MIDDLE  ALT=\"%283-1%29%2F%289-7%29+=+1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The slope of the line joining (6,4) and (4,6) is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%286-4%29%2F%284-6%29+=+-1 ALIGN=MIDDLE  ALT=\"%286-4%29%2F%284-6%29+=+-1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "They are  perpendicular because the product of the slopes is equal to -1.\r<BR>\n" );
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document.write( "The answer is perpendicular. </SPAN>\n" );
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