8. (4x-1) (5x+7)-(1-4x) + (4x-1) (3x + 2) = 0 .

Решим уравнение:

1. $$(4x - 1)(5x + 7) - (1 - 4x) + (4x - 1)(3x + 2) = 0$$ $$20x^2 + 28x - 5x - 7 - 1 + 4x + 12x^2 + 8x - 3x - 2 = 0$$ $$32x^2 + 32x - 10 = 0$$ $$16x^2 + 16x - 5 = 0$$

2. Найдем дискриминант:

   $$D = b^2 - 4ac = (16)^2 - 4 \cdot 16 \cdot (-5) = 256 + 320 = 576$$

3. Найдем корни:

   $$x_1 = \frac{-b + \sqrt{D}}{2a} = \frac{-16 + \sqrt{576}}{2 \cdot 16} = \frac{-16 + 24}{32} = \frac{8}{32} = \frac{1}{4} = 0.25$$ $$x_2 = \frac{-b - \sqrt{D}}{2a} = \frac{-16 - \sqrt{576}}{2 \cdot 16} = \frac{-16 - 24}{32} = \frac{-40}{32} = -\frac{5}{4} = -1.25$$

Ответ: x = 0.25, x = -1.25