Lekoev

Ответ:

1)4 2)4 3)7

Пошаговое объяснение:

1) 6x = 28-x

6x + x = 28

7x = 28

x = 4

2) 9x-26 = 30-5x

9x+5x = 30+26

14x = 56

x = 56/14

x = 4

3)7-3x = 6x-56

7+56 = 3x+6x

63 = 9x

x = 7