Final answer:
To simplify 3x(-4x-5), distribute the 3x to -4x and -5, then combine like terms to find -12x² - 15x. The coefficient of x² is -12.
Step-by-step explanation:
To simplify the expression 3x(-4x-5), we can use the distributive property. First, distribute the 3x to both terms inside the parentheses: 3x * -4x = -12x² and 3x * -5 = -15x. Next, combine the resulting terms: -12x² - 15x. The coefficient of x² is -12.
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