4. Решите уравнение 36 - (6 - x)² = x(2,5 - x).

36 - (6 - x)² = x(2.5 - x)
36 - (36 - 12x + x²) = 2.5x - x²
36 - 36 + 12x - x² = 2.5x - x²
12x - x² = 2.5x - x²
12x - 2.5x = 0
9.5x = 0
x = 0

**Ответ:** x = 0