4) (6x-1)² - (5x+2)(6x+5) = 6(x-1)² - 37x;

Решение: $$(36x^2 - 12x + 1) - (30x^2 + 25x + 12x + 10) = 6(x^2 - 2x + 1) - 37x$$ $$36x^2 - 12x + 1 - 30x^2 - 37x - 10 = 6x^2 - 12x + 6 - 37x$$ $$6x^2 - 49x - 9 = 6x^2 - 49x + 6$$ $$-9 = 6$$ Решений нет.