Question

Use foil method (8a - 8)(4a + 1)

Answer 1

The answer is:  " 32a² − 24a − 8 " .
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Given:
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(8a − 8)(4a + 1) ;  Let us expand this expression using the:  "FOIL" method.
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"FOIL" stands for "First terms, Outer terms,  Inner Terms, Last Terms" ;
           in that order.
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Basically:
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(a + b)(c + d) = ac + ad + bc + bd ;

in which the:

First term is:    "ac" ;
Outer term is:  "ad" ;
I nner term is:   "bc" ;
Last term is:    "bd " .
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So; we have (given):

(8a − 8)(4a + 1) ;
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Let's take the "First, Outer,  Inner, and Last terms" ; as follows:
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F:  (8a)*(4a) = 32a² ;
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O:  (8a)*(1) = 8a ;
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I :   (-8)*(4a) = -32a ;
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L:  (-8)*(1) = -8
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Now, let us write out these terms:
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  32a² + 8a − 32a - 8 ;
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Now, combine the "like terms" in this expression; to simplify:

       + 8a − 32a = -24a ;
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and rewrite the simplified expression ; which is:
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        32a² − 24a − 8 .
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