d) 5xy – 25x² + 50x – 10y.

d) Cách 1:

5xy – 25x² + 50x – 10y

= (5xy – 25x²) + (50x – 10y)

= 5x(y ‒ 5x) + 10(5x ‒ y)

= 5x(y ‒ 5x) ‒ 10(y ‒ 5x)

= 5(y ‒ 5x)(x ‒ 2).

Cách 2:

5xy – 25x² + 50x – 10y

= (5xy – 10y) – (25x² – 50x)

= 5y(x – 2) – 25x(x – 2)

= 5(x – 2)(y – 5x).