Помогиекееее срочнооор

Решите задачу:

$2x(x {}^{2} + 36x + 324) - x {}^{3} - 18x {}^{2} = 0 \\ 2x { }^{3} + 72x {}^{2} + 648x - x {}^{3} - 18x {}^{2} = 0 \\ x {}^{3} + 54x {}^{2} + 648x = 0 \\ x(x {}^{2} + 54x + 648) = 0 \\ x(x {}^{2} + 36x + 18x + 648) = 0 \\ x(x(x + 36) + 18(x + 36)) = 0 \\ x(x + 36)(x + 18) = 0 \\ x = 0 \\ x + 36 = 0 \\ x + 18 = 0 \\ x = 0 \\ x = - 36 \\ x = - 18$