document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=145375>Question 145375</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me solve this question. Which of the following relations is (are) functions?\r<BR>\n" );
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document.write( "a.  {(x,y)| y^2=2x+1}<BR>\n" );
document.write( "b.  {(x,y)| y=2x^2+1}<BR>\n" );
document.write( "c.  {(2,3), (3,3), (4,3)} </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #106251 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=106251\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Please help me solve this question. Which of the following relations is (are) functions? <BR>\n" );
document.write( "a. {(x,y)| y^2=2x+1}<BR>\n" );
document.write( "Solve for \"x\" : x = (y^2-1)/2<BR>\n" );
document.write( "This is a parabola opening to the right.<BR>\n" );
document.write( "It is not a function.<BR>\n" );
document.write( "Notice that when x = 0, y^2 = 1, so y could be +1 or it could be -1.<BR>\n" );
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document.write( "b. {(x,y)| y=2x^2+1}<BR>\n" );
document.write( "This is a prabola opeing up and is a function.<BR>\n" );
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document.write( "c. {(2,3), (3,3), (4,3)}<BR>\n" );
document.write( "Each different x value has a unique y-value paired with it.<BR>\n" );
document.write( "It is a function.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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