Bonjour,

Développer chaque expressions:

H= (a+7)(a+2)

H= a²+7a+2a+14

H= a²+9a+14

J= (5+2x)(3x-4)

J= 15x+6x²-20-8x

J= 6x²+7x-20

K= (-4t-2)(3t-10)

K= -12t²-6t+40t+20

K= -12t²+34t+20

L= (x+9)(5x-3) + 4(2x-5)

L= 5x²+45x-3x-27+8x-20

L= 5x²+50x-47