Bonsoir quelqun peut m'aider svp merci

Bonjour,

A = 5/7 + 2/7 + 3/4

A = 7/7 + 3/4

A = 1 + 3/4

A = (1 x 4) / (1 x 4) + 3/4

A = 4/4 + 3/4

A = 7/4

B = 7/4 - 3/4 x 8/9

B = 7/4 - 24/36

B = (7 x 9) / (4 x 9) - 24/36

B = 63/36 - 24/36

B = 39/36

B = (3 x 13) / (3 x 12)

B = 13/12

C = 3/8 + 5/4 x 7/10

C = 3/8 + 35/40

C = (3 x 5) / (8 x 5) + 35/40

C = 15/40 + 35/40

C = 50/40

C = (10 x 5) / (10 x 4)

C = 5/4

D = (1 - 2/3) : (1 + 2/3)

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

D = (3/3 - 2/3) : (3/3 + 2/3)

D = 1/3 : 5/3

D = 1/3 x 3/5

D = 3/3 x 1/5

D = 1/5