Bonjour Exercices 33,34 et 36 svp c'est très urgent

bonjour

a = - 32/45 

b = - 45/54

c= 48/63 = 16/21

d = - 72/11

n°34

a = 9/23

b = 17/12

c = 40/9

d = 3/88

n° 36

a = 70/30 + 27/30 = 97/30

b = 16/120 + 45/120 = 61/120

c = - 13/9 + 45/9 = - 32/9

d =  - 32/8 - 9/8 = - 41/8