5 Решите уравнение: a) (3x - 2)(3x + 2) - (3x - 8)² = 14x; б) 25х2 - 36 - (0.

a) $$(3x - 2)(3x + 2) - (3x - 8)^2 = 14x$$ $$9x^2 - 4 - (9x^2 - 48x + 64) = 14x$$ $$9x^2 - 4 - 9x^2 + 48x - 64 = 14x$$ $$48x - 68 = 14x$$ $$48x - 14x = 68$$ $$34x = 68$$ $$x = 2$$

Ответ: x = 2

б) $$25x^2 - 36 = 0$$ $$25x^2 = 36$$ $$x^2 = \frac{36}{25}$$ $$x = \pm \sqrt{\frac{36}{25}} = \pm \frac{6}{5}$$

Ответ: $$x = \pm \frac{6}{5}$$