document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=8961>Question 8961</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am having trouble with FOIL, and was wondering if you could tell me how to get the answer to (9a-7)(9a + 7)\r<BR>\n" );
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document.write( "Thanks,<BR>\n" );
document.write( "Kyle Pruden </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #4877 by </B><A HREF=/tutors/aboutme.mpl?userid=longjonsilver><B>longjonsilver(2297)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=longjonsilver><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=longjonsilver><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=4877\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> things like FOIL are some of my personal bugbears in maths and maths teaching.\r<BR>\n" );
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document.write( "Why spend time learning something like that when all you need know is what the hell you are supposed to be doing in the first place?\r<BR>\n" );
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document.write( "Right then:\r<BR>\n" );
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document.write( "you have 2 brackets<BR>\n" );
document.write( "each bracket has 2 terms in it<BR>\n" );
document.write( "each of the 2 terms in the first bracket needs to be multiplies with each of the 2 terms in the second bracket. Period!\r<BR>\n" );
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document.write( "As to the order you do this, it does not matter one jot! However, most people seem to take the first 9a and multiply it to the 2 terms in the second bracket and then take the second term (the -7) and multiply it to the 2 terms in the second bracket too.\r<BR>\n" );
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document.write( "So we end up with 4 terms, namely <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%289a%29%2A%289a%29+%2B+%289a%29%2A%287%29+%2B+%28-7%29%2A%289a%29+%2B+%28-7%29%2A%287%29 ALIGN=MIDDLE  ALT=\"%289a%29%2A%289a%29+%2B+%289a%29%2A%287%29+%2B+%28-7%29%2A%289a%29+%2B+%28-7%29%2A%287%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > --> written out long-windedly. This becomes:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=81a%5E2+%2B+63a+-+63a+-+49 ALIGN=MIDDLE  ALT=\"81a%5E2+%2B+63a+-+63a+-+49\"   DISABLED_style= \"max-width:90%; height:auto;\" > which simplifies, in this case to\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=81a%5E2+-+49 ALIGN=MIDDLE  ALT=\"81a%5E2+-+49\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "jon.\r<BR>\n" );
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