Mathematique.. besoin d'aide s'ilbouplait merci bcm

Bonsoir,

A = 1/3 x - 4/5
A = - 4/15

B = 2,2/5 x - 3/5
B = - 6,6/ 25

C = - 10/3 x - 5/7
C = 50/21

D = - 8/3 x 3/4 x 5/7
D = - 24/12 x 5/7
D = - 120/84
D = 12 x - 10 / 12 x 7
D = - 10/7