bonjour,
A ) 2 x = 2 = 2
2 x = 2 + 2
2 x = 4 ⇔ x = 2
b ) 3 z - 10 = 11
3 z = 11 + 10
3 z = 21 ⇔ z = 7
c) 1 - y = 0 ⇔ y = - 1
d) 1 + 5 x = - 39
5 x = - 39 - 1
5 x = - 40 ⇔ x = - 8
e) 2 + 3 z = 9
3 z = 9 - 2
3 z = 7 ⇔ z = 7/3
f) 6 - y = 2.3
- y = 2.3 - 6
- y = - 3.7 ⇔ y = 3.7