27x + 15(3-7x) = 3x(13-8) - 12*(36/3)

27x + 153 - 157x = 3x5 - 1212

27x + 45 - 105x = 15x - 144

-78x + 45 = 15x - 144

-78x - 15x = -144 - 45

-93x = -189

x = -189 / -93

x ≈ 2.0323

Ответ: x ≈ 2.0323.