Explications étape par étape:

i ) 2x + 3 = 5

2x = 5 - 3

2x = 2

2x/2 = 2/2

x = 1

ii ) 3x + 8 = 1

3x = 1 - 8

3x = -7

3x/3 = -7/3

x = -7/3

iii ) -5x + 2 = -3

-5x = -3 - 2

-5x = -5

-5x/-5 = -5/-5

x = 1

iv ) -3x - 1 = 2

-3x = 2 + 1

-3x = 3

-3x/-3 = 3/-3

x = -1