Je dois faire ses deux exs pour demain

bonsoir

a)
x = -5/4
b)
7x = -3-2
7x = -5
x = -5/7
c)
4x+2x =7
6x =7
x =7/6
d)
3x+3x = 8+4
6x = 12
x = 12/6
x = 2

exercice 2

4x -7x = 4 +5
-3x = 9
x = -9/3
x = -3

-2x-4x = 26-8
-6x = 18
x=  -18/6
x =  -3