document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1030970>Question 1030970</A>: <I><SPAN STYLE=\"word-break: break-all;\"> find the equation of the graph of all points such that the difference of their distances from (4,0) and (-4,0) is always equal to 2.<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 #645787 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=645787\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let (x,y) be a point on the curve.\r<BR>\n" );
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document.write( "Then <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28%28x%2B4%29%5E2+%2B+y%5E2%29+-+sqrt%28%28x-4%29%5E2+%2B+y%5E2%29+=+2 ALIGN=MIDDLE  ALT=\"sqrt%28%28x%2B4%29%5E2+%2B+y%5E2%29+-+sqrt%28%28x-4%29%5E2+%2B+y%5E2%29+=+2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "==> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28%28x%2B4%29%5E2+%2B+y%5E2%29+=+sqrt%28%28x-4%29%5E2+%2B+y%5E2%29+%2B+2 ALIGN=MIDDLE  ALT=\"sqrt%28%28x%2B4%29%5E2+%2B+y%5E2%29+=+sqrt%28%28x-4%29%5E2+%2B+y%5E2%29+%2B+2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "==> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x%2B4%29%5E2+%2B+y%5E2+=+%28x-4%29%5E2+%2B+y%5E2+%2B+4sqrt%28%28x-4%29%5E2+%2B+y%5E2%29+%2B4 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >, after squaring both sides...\r<BR>\n" );
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document.write( "==> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4x+-+1+=+sqrt%28%28x-4%29%5E2+%2B+y%5E2%29 ALIGN=MIDDLE  ALT=\"4x+-+1+=+sqrt%28%28x-4%29%5E2+%2B+y%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, after reducing further..\r<BR>\n" );
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document.write( "==> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=16x%5E2+-+8x+%2B1+=+x%5E2+-+8x%2B16+%2By%5E2 ALIGN=MIDDLE  ALT=\"16x%5E2+-+8x+%2B1+=+x%5E2+-+8x%2B16+%2By%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > after squaring both sides.\r<BR>\n" );
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document.write( "==> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=15x%5E2+-+y%5E2+=+15 ALIGN=MIDDLE  ALT=\"15x%5E2+-+y%5E2+=+15\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "==> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2+-+y%5E2%2F15+=+1 ALIGN=MIDDLE  ALT=\"x%5E2+-+y%5E2%2F15+=+1\"   DISABLED_style= \"max-width:90%; height:auto;\" >, which is a hyperbola center at (0,0) and x-axis as transverse axis. </SPAN>\n" );
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