document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=213768>Question 213768</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Is a circle a 'function' - it does not pass the vertical line test.  tks!\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 #161494 by </B><A HREF=/tutors/aboutme.mpl?userid=drj><B>drj(1380)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=drj><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=drj><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=161494\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Is a circle a 'function' - it does not pass the vertical line test.  tks!\r<BR>\n" );
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document.write( "Yes.  You are correct.  But it is an equation like <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2By%5E2=1 ALIGN=MIDDLE  ALT=\"x%5E2%2By%5E2=1\"   DISABLED_style= \"max-width:90%; height:auto;\" > centered at (0,0) or radius 1.  So at x=0 then y has two possible values at +1 and -1.\r<BR>\n" );
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document.write( "Hope that was helpful!.\r<BR>\n" );
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document.write( "I hope the above steps were helpful. \r<BR>\n" );
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document.write( "And good luck in your studies!\r<BR>\n" );
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document.write( "For free Step-By-Step Videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.\r<BR>\n" );
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document.write( "Respectfully,<BR>\n" );
document.write( "Dr J </SPAN>\n" );
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