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       #Post#: 99--------------------------------------------------
       DIFFERENCE OF SQUARES
       By: eba95 Date: July 30, 2010, 6:09 am
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       Difference of Squares
       You have all learned that
       a2 - b2 = (a + b)(a - b)
       But perhaps you haven't thought
       about how to use this to do fast
       mental calculations! See if you can
       guess how this trick can help you do
       the following in your head:
       43 x 37
       78 x 82
       36 x 24
       Let's do the first one. 43 x 37 = (40 +
       3)(40 - 3) = 402 - 32 = 1600 - 9 = 1591.
       Practice these, and you'll be able to
       impress your friends!
       Presentation Suggestions:
       See if the class can figure out what
       you are about to do.
       The Math Behind the Fact:
       The moral of the story is if you think
       CREATIVELY about everything that
       you learn in mathematics, even the
       easy stuff like algebra, you will find
       some surprising applications
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