Respuesta :

A=(x+4)(x+3)
=x²+3x+4x+12
=x²+7x+12

B=(y+3)(2y+8)
=2y²+8y+6y+24
=2y²+14y+24

C=(3z+4)(5-6z)
=15z-18z²+20-24z
=18z²-9z+20

D=(-7t+8)(3-5t)
=-21t+35t²+24-40t
=35t²-61t+24