document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=255306>Question 255306</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Why is the line x=4 a vertical line?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #187585 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=187585\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Why is the line x=4 a vertical line?<BR>\n" );
document.write( "Plot any two points points that satisfy<BR>\n" );
document.write( "the condition.<BR>\n" );
document.write( "Example: (4,-3),(4,2)<BR>\n" );
document.write( "Draw a line thru the two points.<BR>\n" );
document.write( "Notice that the line is vertical.<BR>\n" );
document.write( "---<BR>\n" );
document.write( "Also, determine the slope of the line.<BR>\n" );
document.write( "slope = (2--3)/(4-4) = 5/0 which is undefined<BR>\n" );
document.write( "---<BR>\n" );
document.write( "Any line which has an undefined slope is vertical.<BR>\n" );
document.write( "Any vertical line has an undefined slope.<BR>\n" );
document.write( "---<BR>\n" );
document.write( "Any equation of the form y = k, where k is some number,<BR>\n" );
document.write( "graphs as a vertical line.<BR>\n" );
document.write( "=======================================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.  </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );