Tìm x, biết: a) \(3x(12x - 4) - 9x(4x - 3) = 30\); b) \((12x - 5)(4x - 1) + (3x - 7)(1 - 16x) = 81\)
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Bài 7. Tìm x, biết
a) \(3x(12x - 4) - 9x(4x - 3) = 30\).
b) \((12x - 5)(4x - 1) + (3x - 7)(1 - 16x) = 81\).
c) \(x^2 - 4x + 4 = 25\).
d) \(3(2x - 1)(3x - 1) - (2x - 3)(9x - 1) = 0\).