document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1142369>Question 1142369</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me solve this:\r<BR>\n" );
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document.write( "Which of the following defines a one  -  to  -  one function / define one  -  to  -  one functions in x?\r<BR>\n" );
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document.write( "A. y = x^2 <BR>\n" );
document.write( "B. x = y^2 <BR>\n" );
document.write( "C. xy = 1\r<BR>\n" );
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document.write( "1. Only A <BR>\n" );
document.write( "2. Only B <BR>\n" );
document.write( "3. Only C<BR>\n" );
document.write( "4. Only A and B <BR>\n" );
document.write( "5. Only A </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #763159 by </B><A HREF=/tutors/aboutme.mpl?userid=math_helper><B>math_helper(2461)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math_helper><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=math_helper><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=763159\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "I realize you are probably a high school student learning about functions for the first time.  You should attempt this on your own because it is fundamental to understanding a lot of math that will follow.  The posting of this question comes across as someone who does not want to exert the effort needed to learn. <br>\r<BR>\n" );
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document.write( "I will give you this hint: a function requires that a vertical line (a line parallel to the y-axis) cross the graph of that function no more than once, for ANY x-value that you choose to put that line on. My recommendation is for you to graph the three functions and see which pass this test.   Post/message what you think the answer is and I will help you from there.  The site desmos.com is an excellent graphing utility.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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