document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=68580>Question 68580</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Are the following lines parallel, perpendicular, or neither?<BR>\n" );
document.write( "   L1 through (–4, –7) and (1, 3)<BR>\n" );
document.write( "   L2 through (2, 6) and (4, 10)<BR>\n" );
document.write( "a)Parallel<BR>\n" );
document.write( "b)Perpendicular<BR>\n" );
document.write( "c)Neither\r<BR>\n" );
document.write( "\n" );
document.write( "The answer I got for this one was perpendicular. Is this correct? If not could you show me how to do this the right way. Thanks.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #48814 by </B><A HREF=/tutors/aboutme.mpl?userid=Earlsdon><B>Earlsdon(6294)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Earlsdon><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=48814\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Remember the rule?<BR>\n" );
document.write( "\"Perpendicular lines have slopes that are the negative reciprocal of each other.\"<BR>\n" );
document.write( "\"Parallel lines have identical slopes\"<BR>\n" );
document.write( "So first, we need to find the slopes of the lines through the given points.<BR>\n" );
document.write( "Using the slope formula: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m+=+%28y2-y1%29%2F%28x2-x1%29 ALIGN=MIDDLE  ALT=\"m+=+%28y2-y1%29%2F%28x2-x1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "For the first slope, (x1, y1) = (-4, -7) and (x2, y2) = (1, 3)<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m1+=+%283-%28-7%29%29%2F%281-%28-4%29%29 ALIGN=MIDDLE  ALT=\"m1+=+%283-%28-7%29%29%2F%281-%28-4%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Simplify.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m1+=+%283%2B7%29%2F%281%2B4%29 ALIGN=MIDDLE  ALT=\"m1+=+%283%2B7%29%2F%281%2B4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m1+=+10%2F5 ALIGN=MIDDLE  ALT=\"m1+=+10%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m1+=+2 ALIGN=MIDDLE  ALT=\"m1+=+2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Similarly for the second slope, m2.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m2+=+%2810-6%29%2F%284-2%29 ALIGN=MIDDLE  ALT=\"m2+=+%2810-6%29%2F%284-2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Simplify.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m2+=+4%2F2 ALIGN=MIDDLE  ALT=\"m2+=+4%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m2+=+2 ALIGN=MIDDLE  ALT=\"m2+=+2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Well, as you can see, the slopes of the two lines are identical which means that the lins are parallel.<BR>\n" );
document.write( "You might want to review your work on this problem! </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );