document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=141027>Question 141027</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0131469002/algebrahomeworkh>Intermediate Alebra A Graphing Approach</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Is there an easier way to phrase the instructions in book? I am not understanding the examples and phases in the book.After finding the domain and range, just how can you tell if it's a function or not. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #102768 by </B><A HREF=/tutors/aboutme.mpl?userid=rapaljer><B>rapaljer(4671)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rapaljer><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=rapaljer><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=102768\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You might want to see  my explanations of the topics.  For additional explanation on the topic of Domain and Range, see my own website by clicking on my tutor name \"rapaljer\" anywhere in algebra.com. Take the third link on my homepage which is \"Math in Living Color\", click on \"College Algebra\" and look for Chapter 2, Section 2.07 Functions, Domain, and Range.  This is a section of problems that I have solved in LIVING COLOR, with an explanation written for folks who didn't get math the first time!! \r<BR>\n" );
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document.write( "As to your specific question, \"How do you tell if something is a function or not?\", there are two perspectives.  First to look at the graph of the function.  If you can graph it (and if you have a graphing calculator, this can be a HUGE help for you!!), use what we call the \"vertical line test\".  If ANY vertical line intersects the graph in more than one point, then it is NOT a function.\r<BR>\n" );
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document.write( "More specifically, if you have an equation of an equation in x and y, if this equation has a y= + or -, then it is NOT a function!  Secondly, if the equation has a y^2, y^4, y^(even) power, then it is NOT a function.  However, if you can solve for y, and write this in the form of \"y=______\", then it IS a function.  Maybe this will help in most problems.  Do you have specific equations in mind?\r<BR>\n" );
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document.write( "R^2<BR>\n" );
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