Which equation is equivalent to 3[x + 3(4x – 5)] = 15x – 24?

First distribute 3 inside the brackets: 3(4x − 5) = 12x − 15. Then add x to get 13x − 15, and multiply the entire expression by 3 to get 39x − 45. Thus the equivalent equation is 39x − 45 = 15x − 24, choice C.

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