Bonsoirs pouvez-vous m'aidez s'il vous plait ? mercii

Bonjour

1)

A = - 5 + 4 - (- 5) - 3 - 1

A = - 5 + 4 + 5 - 3 - 1

A = - 5 + 5 + 4 - 1 - 3

A = 0.

B = 7 x 8 + 9 x (- 9 + 3)

B = 56 + 9 x (- 6)

B = 56 - 54

B = 2.

2)

C = 1/9 - 15/9 x 1/6 + 2/3

C = 1/9 - 15/54 + 2/3

C = (1 x 6) / (9 x 6) - 15/54 + (2 x 18) / (3 x 18)

C = 6/54 - 15/54 + 36/54

C = 42/54 - 15/54

C = 27/54

C = (27 x 1) / (27 x 2)

C = 1/2

D = 15 : (1/4 - 2/3)

D = 15 : [(1 x 3) / (4 x 3) - (2 x 4) / (3 x 4)]

D = 15 : (3/12 - 8/12)

D = 15 : (- 5/12)

D = 15 x (- 12/5)

D = - 180/5

D = (5 x - 36) / (5 x 1)

D = - 36.