document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=211397>Question 211397</A>: <I><SPAN STYLE=\"word-break: break-all;\"> if 6 is added to a number and then subtracted from the same number, the product of the sum and the difference is 189. What is the number?<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 #159756 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=159756\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let x = the number<BR>\n" );
document.write( "x+6 = the \"sum\"<BR>\n" );
document.write( "x-6 = the \"difference\"\r<BR>\n" );
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document.write( "The equation is:\r<BR>\n" );
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document.write( "(x+6)(x-6) = 189\r<BR>\n" );
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document.write( "x^2 -36 = 189\r<BR>\n" );
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document.write( "Since this is quadratic, set it equal to zero:<BR>\n" );
document.write( "x^2 -36-189=0<BR>\n" );
document.write( "x^2-225=0\r<BR>\n" );
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document.write( "There are two ways to solve this.  You can factor it:<BR>\n" );
document.write( "(x-15)(x+15) = 0<BR>\n" );
document.write( "x=15 or x=-15\r<BR>\n" );
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document.write( "Or you can use the square root method:<BR>\n" );
document.write( "x^2 -225 =0<BR>\n" );
document.write( "x^2=225<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=+sqrt%28225%29 ALIGN=MIDDLE  ALT=\"x=+sqrt%28225%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=+-sqrt%28225%29 ALIGN=MIDDLE  ALT=\"x=+-sqrt%28225%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+15 ALIGN=MIDDLE  ALT=\"x+=+15\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=-15 ALIGN=MIDDLE  ALT=\"x=-15\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "R^2\r<BR>\n" );
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document.write( "Dr. Robert J. Rapalje, Retired<BR>\n" );
document.write( "Seminole Community College\r<BR>\n" );
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