в) \(\frac{1}{3}\)(3x - 6) - \(\frac{2}{7}\)(7x - 21) = 9; г) 5,4(Зу - 2) - 7,2(2y-3) = 1,2.

в)

\(\frac{1}{3}\)(3x - 6) - \(\frac{2}{7}\)(7x - 21) = 9

x - 2 - 2x + 6 = 9

-x + 4 = 9

-x = 5

x = -5

Ответ: x = -5

г)

5,4(3y - 2) - 7,2(2y - 3) = 1,2

16,2y - 10,8 - 14,4y + 21,6 = 1,2

1,8y + 10,8 = 1,2

1,8y = -9,6

y = -\(\frac{9,6}{1,8}\)

y = -\(\frac{16}{3}\)

Ответ: y = -\(\frac{16}{3}\)