bonsoir
A = 21 + 1.5 x
B = 5 x
A ( 8) = 21 + 1.5 x 8 = 33
B ( 8) = 40
21 + 1.5 x = 5 x
1.5 x - 5 x = - 21
- 3.5 x = - 21
x = 6
A = B pour 6 séances
