Pourriez vous m'aider SVP! un quart de x = 5 tiers puis -2x/3 = 4/7 et 2x-2/3 =5/2 merci beaucoup par avance!!!!!!

1/4x = 5
x = 5 * 4
x = 20

- 2x/3 = 4/7
- 2x * 7 = 4 * 3
- 14x = 12
x = - 12/14
x = - 6/7

2x - 2/3 = 5/2
2x = 5/2 + 2/3
2x = 15/6 + 4/6
2x = 19/6
x = 19/6 * 1/2
x = 19/12

1) x/4 = 5/3
x=20/3
2) -2x/3 = 4/7
-2x = 12/7
-x = 6/7
x = - 6/7
3) 2x -2/3 = 5/2
2x = 5/2 + 2/3
2x = 40/6
2x = 20/3
x = 10/3