Bonjour pouvez-vous m’aider pour cet exercice de maths s’il vous plaît ?

Bonjour

A = 1 - - 7/3

A = 1 + 7/3

A = (1 x 3) / (1  x 3) + 7/3

A = 3/3 + 7/3

A = 10/3

B= - 2/10 + 7/25

B = (- 2 x 5) / (10 x 5) + (7 x 2) / (25 x 2)

B = - 10/50 + 14/50

B = 4/50

B = (2 x 2) / (2 x 25)

B = 2/25

C = - 7/15 x (- 5/21)

C = 35/315

C = (35 x 1) / (35 x 9)

C = 1/9

D = - 7/3 + - 21/6

D = (- 7 x 2) / (3 x 2) - 21/6

D = - 14/6 - 21/6

D = - 35/6.