3. Решить уравнение: a) $$4(3x + 0,5) = 6x - (3x + 4)$$ б) $$(x - 2)^2 = x(x + 2)$$

a) $$4(3x + 0,5) = 6x - (3x + 4)$$
$$12x + 2 = 6x - 3x - 4$$
$$12x + 2 = 3x - 4$$
$$12x - 3x = -4 - 2$$
$$9x = -6$$
$$x = -\frac{6}{9} = -\frac{2}{3}$$
Ответ: $$x = -\frac{2}{3}$$
б) $$(x - 2)^2 = x(x + 2)$$
$$x^2 - 4x + 4 = x^2 + 2x$$
$$x^2 - 4x - x^2 - 2x = -4$$
$$-6x = -4$$
$$x = \frac{-4}{-6} = \frac{2}{3}$$
Ответ: $$x = \frac{2}{3}$$