Réponse :Bonjour,

A = x -( 1/3)x =x(1-1/3) = x(3/3 - 1/3) = x(2/3)= (2/3)*x ou 2x/3

B= 9x - 5x =x(9-5) = 4x

C = 1xy -4xy = (1-4)xy = -3xy

D = 5y(3x + 2)

E= ab(5-9+1) = ab(-4+1) = ab (-3) = -3ab

F = x² (2-7+3) = -2x²