Réponse:
Coucou !
a)
9x-18=0
9x=18
9x/9=18/9
x=2
b)3(10x+15)=0
3×10x+3×15=0
30x+45=0
30x=-45
30x/30=-45/30
x=-1,5
c)3x+4=5x-10
3x=5x-10-4
3x-5x=10-4
-2x=6
-2x/-2=6/-2
x=-3
d)7(x+8)=4(2x-10)
7×x+7×8=4×2x+4×(-10)
7x+56=8x-40
7x=8x-40-56
7x=8x-96
7x-8x=-96
-1x=-96
-1x/-1=-96/-1
x=96
Bon courage