document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=901776>Question 901776</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Good day\r<BR>\n" );
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document.write( "I have something puzzling me for quite a while now\r<BR>\n" );
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document.write( "Let't take an example \r<BR>\n" );
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document.write( "In the quadratic equation\r<BR>\n" );
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document.write( "1.  72c2 + 24c - 16\r<BR>\n" );
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document.write( "The answer is (12c - 4) (6c + 4)\r<BR>\n" );
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document.write( "Firstly.. Why 12 and 6? why not something like 9 and 8<BR>\n" );
document.write( "Tried the formula with this example numbered as \"1.\"\r<BR>\n" );
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document.write( "Secondly.. How do I know from the equation \"72c2 + 24c - 16\" which bracket is going to get the \"+\" and which bracket is going to get the \"-\"\r<BR>\n" );
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document.write( "They explained it in school but I just can't remember the principles.\r<BR>\n" );
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document.write( "Kind Regards.\r<BR>\n" );
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document.write( "Stefan. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #546969 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=546969\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In the quadratic equation\r<BR>\n" );
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document.write( "1.  72c2 + 24c - 16<BR>\n" );
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document.write( "That's not an equation, there's no equal sign.<BR>\n" );
document.write( "The answer is (12c - 4) (6c + 4)<BR>\n" );
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document.write( "I would say it's 8*(3c-1)*(3c+2)<BR>\n" );
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document.write( "The short answer is, because 9 and 8 don't work.  If you factor out the 8 first, it's obvious it can't be 9 and 8.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=72c%5E2+%2B+24c+-+16+=+8%289c%5E2+%2B+3c+-+2%29 ALIGN=MIDDLE  ALT=\"72c%5E2+%2B+24c+-+16+=+8%289c%5E2+%2B+3c+-+2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Then you might ask, \"Why 3 and 3, and not 9 and 1?\"<BR>\n" );
document.write( "You can't get the middle term to be 3c using 9 and 1.<BR>\n" );
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document.write( "Factor out any coefficients first, it'll make it simpler.<BR>\n" );
document.write( "Use ^ (Shift 6) for exponents.<BR>\n" );
document.write( "eg, c^2 </SPAN>\n" );
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