Sagot :

Bonjour,

(x+4)(2x-5)+(x+4)(6x-3)

= (x+4)[(2x-5)+(6x-3)]

= (x+4)(8x-8)

= 8(x+4)(x-1)

(2x-5)²-25

= (2x-5)² - 5²

= (2x-5+5)(2x-5-5)      car a²-b² = (a+b)(a-b)

= 2x(2x-10)