My Algebra teacher was explaining to the class about creating a trinomial using FOIL. What is it, and how is it done?
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1Also wiki: Foil Method. – J. W. Perry Sep 13 '14 at 22:39
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6Forget about Foil, it is for little old school marms, study the distributive law. – Rene Schipperus Sep 13 '14 at 22:41
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Why was this question down voted? – Scribblenautical Sep 13 '14 at 22:47
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2I dont know why this was downvoted, but there is a systematic program by a small number of users to downvote and close questions not meeting their "standards". – Rene Schipperus Sep 13 '14 at 22:52
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FOIL is a mnemonic for how to multiply thing in the form $(a+b)*(c+d)$
$$(a+b)*(c+d)=ac+ad+bc+bd$$
This is you add up the **F**irst terms (ac) , **O**utside terms (ad) , **I**nside terms (bc), and **L**ast terms (bd)
Its just another way to simplify this type of multiplication.
Asimov
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7How is my simple explanation of a simple mnemonic worth 3 upvotes when my more in depth analyses are ignored on other problems? #stackexchangeproblems – Asimov Sep 13 '14 at 22:42
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1@mathtastic Thats a good point, but as a reasonably advanced math student, I shall choose to ignore it. – Asimov Sep 13 '14 at 22:57
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2Did I mention that my highest rated answer of all time has to do with explaining what a percent means? 17 upvotes for that one. – Asimov Sep 13 '14 at 23:04
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