Verified answer

Объяснение:

1)

9х = 2/5

х = 2/5 : 9

х = 2/5 * 9

х = 18/5

х = 3 3/5

2)

3х = 2

х = 2 : 3

х = 2/3

3)

1/2х = 3

х = 3 : 1/2

х = 3 * 2/1

х = 6/1

х = 6

4)

3/4х = 1/2

х = 1/2 : 3/4

х = 1/2 * 4/3

х = 4/6

х = 2/3