a. 2 x (x + 3) = 2 x ... +2 x... b.5x (7 - y) = 5 x ... -5x... c. 6(x + 11) = 6 x ... + ... X ... d.3(2y + 1) = 3 x ... +... X1 .

Réponse:

a = 2×x+2×3

= 2x+6

b = 5×7-5×y

= -5y+35

c = 6×x+6×11

= 6x+66

d = 3×2y+3×1

= 6y+3

a.  2 × (x + 3) = 2 × x + 2x x 3 = 2x + 6x

b.5x (7 - y) = 5x × 7  - 5x ×7 = 35x - 5xy

c. 6(x + 11) = 6 × x  + 6 × 11 = 6x + 66

d.3(2y + 1) = 3 × 2y + 3 × 1 = 6y + 3