document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=91948>Question 91948</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Determine the domain of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f%28a%29+=+%28a%5E2-16%29%2F%28+a%5E2-3a-28%29 ALIGN=MIDDLE  ALT=\"f%28a%29+=+%28a%5E2-16%29%2F%28+a%5E2-3a-28%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "So that is f(a) = a squared - 16 divided by a squared - 3a - 28\r<BR>\n" );
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document.write( "Please help!! Thanks! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #66788 by </B><A HREF=/tutors/aboutme.mpl?userid=mathispowerful><B>mathispowerful(115)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mathispowerful><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=66788\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f%28a%29+=+%28a%5E2-16%29%2F%28+a%5E2-3a-28%29 ALIGN=MIDDLE  ALT=\"f%28a%29+=+%28a%5E2-16%29%2F%28+a%5E2-3a-28%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Let's simplify this expression first\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f%28a%29+=+%28a%2B4%29%28a-4%29%2F%28a-7%29%28a%2B4%29 ALIGN=MIDDLE  ALT=\"f%28a%29+=+%28a%2B4%29%28a-4%29%2F%28a-7%29%28a%2B4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "here a+4 canceled.\r<BR>\n" );
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document.write( "Now we have <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f%28a%29+=+%28a-4%29%2F%28a-7%29 ALIGN=MIDDLE  ALT=\"f%28a%29+=+%28a-4%29%2F%28a-7%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Domain is a collection of all allowed x values.\r<BR>\n" );
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document.write( "in the above expression we have a -7 on the bottom, you know\r<BR>\n" );
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document.write( "it can not be 0, so a -7 can not be 0, that means a can not equal to 7,\r<BR>\n" );
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document.write( "the answer is a can be any real numbers except 7.\r<BR>\n" );
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document.write( "the graph of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f%28a%29+=+%28a%5E2-16%29%2F+%28a%5E2-3a-28%29 ALIGN=MIDDLE  ALT=\"f%28a%29+=+%28a%5E2-16%29%2F+%28a%5E2-3a-28%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > can verify the answer\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28200%2C200%2C+-10%2C+10%2C+-10%2C+10%2C+%28x%5E2-16%29%2F%28x%5E2-3x-28%29%29 ALIGN=MIDDLE  ALT=\"graph%28200%2C200%2C+-10%2C+10%2C+-10%2C+10%2C+%28x%5E2-16%29%2F%28x%5E2-3x-28%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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