bonsoir
a) 5 + 1.5t = 3 + 2.5t
1.5 t - 2.5 t = 3 - 5
- t = - 2
t = 2
b) 3y - 3.5 = 9y -3.5
3 y - 9 y = - 3.5 + 3.5
- 6 y = 0
y = 0
c) 2.5z + 5 = -2.5z - 5
2.5 z + 2.5 z = - 5 - 5
5 z = - 10
z = - 2
d) 0.5t + 1 = 2t + 1.5
0.5 t - 2 t = 1.5 - 1
- 1.5 t = - 0.5
t = 5/15 = 1/3
e) 8y = y + 1.5
8 y - y = 1.5
7 y = 1.5
y = 15/70
y = 3 / 14
f) 7.8i - 8 = 1.3i + 2
7.8 i - 1.3 i = 2 + 8
6.5 i = 10
i = 100/65 = 20/13