Quelqu’un peut m’aider pour la b) et c) entouré

Bonsoir,

b. - 2/3 + 7/8 - 5/6

= (- 2 x 8) / (3 x 8) + (7 x 3) / (7 x 3) - (5 x 4) / (6 x 4)

= - 16/24 + 21/24 - 20/24

= - 36/24 + 21/24

= - 15/24

= (3 x - 5) / (3 x 8)

= - 5/8

c. - 2/10 + 7/25

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

= - 10/50 + 14/50

= 4/50

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

= 2/25.