Resposta:

a) x = 5

b) x = 3

c) x = 4

d) x = 3

e) x = -3

f) x = -7

Explicação passo a passo:

a) 2x - 3=7

2x = 7+3

2x = 10

x = 10/2

x = 5

b) x+2=5

x = 5-2

x = 3

c) 4x + 6 = 22

4x = 22-6

4x = 16

x = 16/4

x = 4

d) 5x-6=2x + 15

5x - 2x = 15-6

3x = 9

x = 9/3

x = 3

e) 3x+9=2x-12

3x - 2x = -12+9

x = -3