Jabarkan bentuk perkalian berikut dengan sifat distributif

A)
(2x – 3)(x + 5)
= (2x)(x) + (2x)(5) + (-3)(x) + (-3)(5)
= 2x² + 10x – 3x – 15
= 2x² + 7x – 15

b)
(3x – y)(x + y)
= (3x)(x) + (3x)(y) + (-y)(x) + (-y)(y)
= 3x² + 3xy – xy – y²
= 3x² + 2xy – y²

c)
(5m – 1)(m + 4)
= (5m)(m) + (5m)(4) + (-1)(m) + (-1)(4)
= 5m² + 20m – m – 4
= 5m² + 19m – 4