Bonjour,
a. 2x-2=2
2x-2+2=2+2
2x=4
2x÷2=4÷2
x=2
b. 3z-10=11
3z-10+10=11+10
3z=21
3z÷3=21÷3
z=7
c. 1-y=0
1-1-y=0-1
-y=-1
-y÷(-1)=-1÷(-1)
y=1
d. 1+5x=-39
1-1+5x=-39-1
5x=-40
5x÷5=-40÷5
x=-8
e. 2+3z=9
2-2+3z=9-2
3z=7
3z÷3=7÷3
z=7/3
