document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1189327>Question 1189327</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A point moves so that its distance from the point (2,-1) is equal to its distance from the x-axis. Find the equation of the <BR>\n" );
document.write( "locus.<BR>\n" );
document.write( "a. x^2  -  4x  -  4y + 4 = 0 <BR>\n" );
document.write( "b. y^2  -  4x  -  2y + 5 = 0 <BR>\n" );
document.write( "c. x^2  -  4x  -  2y + 5 = 0 <BR>\n" );
document.write( "d. x^2 + 4x  -  2y + 5 = 0 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #820655 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52800)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=820655\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "A point moves so that its distance from the point (2,-1) is equal to its distance from the x-axis. <BR>\n" );
document.write( "Find the equation of the locus.<BR>\n" );
document.write( "a. x^2 - 4x - 4y + 4 = 0<BR>\n" );
document.write( "b. y^2 - 4x - 2y + 5 = 0<BR>\n" );
document.write( "c. x^2 - 4x - 2y + 5 = 0<BR>\n" );
document.write( "d. x^2 + 4x - 2y + 5 = 0<BR>\n" );
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document.write( "An equation of the locus is\r\n" );
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document.write( "    <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28%28x-2%29%5E2%2B%28y%2B1%29%5E2%29 ALIGN=MIDDLE  ALT=\"sqrt%28%28x-2%29%5E2%2B%28y%2B1%29%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = |y|.    (notice the absolute value sign in the right side !)\r\n" );
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document.write( "Square both sides of the equation\r\n" );
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document.write( "    (x-2)^2 + (y+1)^2 = y^2\r\n" );
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document.write( "Simplify\r\n" );
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document.write( "    x^2 - 4x + 4 + y^2 + 2y + 1 = y^2\r\n" );
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document.write( "    x^2 - 4x + 2y + 5 = 0.\r\n" );
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document.write( "<U>ANSWER</U>.  The equation of the locus is  x^2 - 4x + 2y + 5 = 0.\r\n" );
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document.write( "         No one of the listed in the options list.\r\n" );
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document.write( "Solved.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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