document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=311155>Question 311155</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Why the line x=4 is 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 #222534 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=222534\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> It's parallel to the y-axis, which is often called vertical.<BR>\n" );
document.write( "It's parallel because for any value of y, x = 4.  It goes thru the points<BR>\n" );
document.write( "(4,0), (4,4), (4,100), any value of y.  That makes it 4 units to the right of the y-axis, parallel to it --> \"vertical\"<BR>\n" );
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document.write( "In 3 axis systems, the y-axis is sometimes horizontal and the z-axis if \"vertical.\"  It's an arbitrary assignment.  If you graph x = 4 and it's vertical, then rotate your graph paper 90º, then it's horizontal.  Use caution in calling it vertical.<BR>\n" );
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