Решите уравнение: x^2/27+x/3=(x+9)/3.

\[\frac{x^{2}}{27} + \frac{x}{3} = \frac{x + 9}{3}\ \ \ \ \ | \cdot 27\]

\[x^{2} + 9x = 9 \cdot (x + 9)\]

\[x^{2} + 9x - 9x = 81\]

\[x^{2} = 81\]

\[x = \pm 9.\]