Tìm x biết: a) 0,6x(x - 0,5) - 0,3x(2x - 1,3) = 0,138. b) 2x(x - 1) - x(4 - x) = 0. c) 5(2x + 3)(x + 2) - 2(5x - 4)(x - 1) = 75

Tìm x biết:
a) 0,6x(x - 0,5) - 0,3x(2x - 1,3) = 0,138
b) 2x(x - 1) - x(4 - x) = 0
c) 5(2x + 3)(x + 2) - 2(5x - 4)(x - 1) = 75
d) 3(2x - 1)(3x - 1) - (2x - 3)(9x - 1) = 0