40 :

A = 5x × 4x = 20x^2

B = 7 × 3x = 21x

C = 4 × 2x^2 = 8x^2

D = 4x × 3 = 12x

E = 5x^2 × 2 = 10x^2

F = 6x × 3x = 18x^2

G = 3a × 2b = 6ab

H = x × 2y = 2yx

I = 2b × 2c = 4bc

Réponse :

bonjour

Explications étape par étape

A=5x*4x=20x²

B=7*3x=21x

C=4*2x²=8x²

D=4x*3=12x

E=5x²*2=10x²

F=6x*3x=18x²

G=3a*2b=6ab

H=x*2y=2xy

I=2b*2c=4bc

*= multiplier