The answer is: -26 √3 .
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Step-by-step explanation:
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Given: " -12√12 − 2√3 " ;
Let us simplify "-12√12 " to a value with "√3" ; 
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 -12√12 = ? ;
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 √12 = √4 * √ 3 = 2√3 ;
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 -12√12 = -12 * 2√3 = -24 √3 ;
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 -12√12 − 2√3 = -24√3 − 2√3 = 
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 -26 √3 .
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