document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=108103>Question 108103</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Determine whether the lines are parallel, perpendicular or neither.\r<BR>\n" );
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document.write( "y = 1/6x - 20<BR>\n" );
document.write( "y = 6x + 15<BR>\n" );
document.write( "and y = 7x - 12 <BR>\n" );
document.write( "y = 7x + 15<BR>\n" );
document.write( "and y = -1/9x + 14<BR>\n" );
document.write( "y = 9x + 16         My answer is Perpendicular to the 1st and 3rd question and the 2nd question is parallel.  I am sure how I know that - can you explain this - I don't know where to start. \r<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 #78743 by </B><A HREF=/tutors/aboutme.mpl?userid=checkley71><B>checkley71(8403)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=checkley71><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=78743\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> IN THE FIRST SET OF 3 NONE ARE PARALLEL NOR PERPENDICULAR.<BR>\n" );
document.write( "SLOPES ARE: 1/6, 6 & 7 NONE EQUAL & NONE THE NEGATIVE RECIPRICAL.<BR>\n" );
document.write( "IN THE SECOND SET OF 3 ONE PAIR ARE PERPENDICULAR.<BR>\n" );
document.write( "HE SECOND HAS A SLOPE OF -1/9 & THE THIRD HAS A SLOPE OF 9 WHICH IS THE NEGATIVE RECIPRICAL OF 9. THEREFORE THESE 2 LINES ARE PERPENDICULAR. <BR>\n" );
document.write( "THE LINES Y=7X-12 & Y=7X+15 ARE PARALLEL LINES BECAUSE THEY HAVE THE SAME SLOPE OF (7).  </SPAN>\n" );
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