15) (45x²y³) : (9x²y²)

15) (45x²y³) : (9x²y²) = (45 : 9) ⋅ (x² : x²) ⋅ (y³ : y²) = 5 ⋅ 1 ⋅ y = 5y

Ответ: 5y