Решите уравнение (5-x)²-x (2,5+x) = 0.

$$(5-x)^2 - x(2.5 + x) = 0$$ $$25 - 10x + x^2 - 2.5x - x^2 = 0$$ $$25 - 12.5x = 0$$ $$12.5x = 25$$ $$x = \frac{25}{12.5} = 2$$ **Ответ:** $$x = 2$$