3. Решите уравнение: a) 132-x²=0 б) 9у² - 36 = 0 в) (3-x)²-x(x+1,5)=9

Решение: a) $$13^2 - x^2 = 0$$ $$169 - x^2 = 0$$ $$x^2 = 169$$ $$x = \pm \sqrt{169}$$ $$x = \pm 13$$ б) $$9y^2 - 36 = 0$$ $$9y^2 = 36$$ $$y^2 = \frac{36}{9}$$ $$y^2 = 4$$ $$y = \pm \sqrt{4}$$ $$y = \pm 2$$ в) $$(3-x)^2 - x(x+1.5) = 9$$ $$9 - 6x + x^2 - x^2 - 1.5x = 9$$ $$9 - 7.5x = 9$$ $$-7.5x = 0$$ $$x = 0$$