Решите уравнение: 81(1/3x-1)(1/9x^2+1/3x+1)-3x(x-2)^2=12x^2.

\[12x = - 81\]

\[x = - \frac{27}{4}\]

\[x = - 6\frac{3}{4}\]

\[Ответ:\ x = - 6\frac{3}{4}\text{.\ }\]