Réponse :
Bonjour
a) 4x = 1/3
x = (1/3)/ 4
x = 1/3*4
x = 1/12
b) 2/5x = 3
x = 3* 5/2
x = 15/2
c) 3/7x = 2/9
x = 2/9 * 7/3
x = 14/27