The answer is: " 56x + 896 " .
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First, simplify the:
(x + 12 + 4) = (x + 16) ;
56(x + 12 + 4) =
56(x + 16) ;
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Note the distributive property of multiplication:
a(b + c) = ab + ac ;
a (b - c) = ab - ac ;
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So;
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56(x + 16) =
56*x + 56*16 =
56x + 896
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