Réponse:
E=(2x-5)(4x-3)-(2x-5)(3x-1)
=(2x-5)[4x-3-(3x-1)]
=(2x-5)[4x-3-3x+1]
E=(2x-5)(x-2)
F=(5x-1)(2x+3)+5x-1
=(5x-1)(2x+3+1)
=(5x-1)(2x+4)
=(5x-1)×2(x+2)
F=2(5x-1)(x+2)