Answer: 
<u>Step-by-step explanation:</u>
Red or Green



≈ 48%
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 "<u>F</u>irst terms, <u>O</u>uter terms, <u> I</u>nner Terms, <u>L</u>ast Terms" ;
in that order.
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Basically:
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(a + b)(c + d) = ac + ad + bc + bd ;
in which the:
<u>F</u>irst term is: "ac" ;
<u>O</u>uter term is: "ad" ;
<u>I </u>nner term is: "bc" ;
<u>L</u>ast term is: "bd " .
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So; we have (given):
(8a − 8)(4a + 1) ;
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Let's take the "<u>F</u>irst, <u>O</u>uter, <u> </u><u>I</u>nner, and <u>L</u>ast terms" ; as follows:
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<u>F</u>: (8a)*(4a) = 32a² ;
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<u>O</u>: (8a)*(1) = 8a ;
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<u>I </u>: (-8)*(4a) = -32a ;
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<u>L</u>: (-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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Answer:
the greatest common factor is 2
He wants $2100 = 30%
2100 is 30% of x
y = p% * x
x = y/p%
x = 2100/30%
30/100 = 0.30
x = 2100/0.30
2100/0.30 = 7000
His monthly net income would need to be $7000