Si vs pouvait m'aider sa serait cool merci d'avance

a) 2x -3 -5 +2x =0
4x -8 = 0
4x = 8
x= 2

b) 2 -6x+3 = 5
-6x = 5-2 -3 
-6x = 0
x=0

c) x -21x + 35 = 2x -10 +15x
-20x +35 = 17x -10
-20x-17x= -10-35
-37x=-45
x=45/37

d) 3x = 8 -x +1 
4x=9 
x=9/4 ,;