(x-3)(x^2+3x+9)-x(x+4)(x-4)=21

Question

(x-3)(x^2+3x+9)-x(x+4)(x-4)=21

Answer 1

—————————————- не 100%

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Answer 2

(x-3)(x^2+3x+9)-x(x+4)(x-4)=21; х^3-27-х*(х^2-16)=21; -27+16х=21; 16х=21+27; 16х=48; х=3. Ответ:х=3

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