2) (4x+1)(x+5) - (2x+1)(2x-3) = 58

Решение: $$(4x+1)(x+5) - (2x+1)(2x-3) = 58$$ $$4x(x+5) + 1(x+5) - [2x(2x-3) + 1(2x-3)] = 58$$ $$4x^2 + 20x + x + 5 - [4x^2 - 6x + 2x - 3] = 58$$ $$4x^2 + 21x + 5 - 4x^2 + 4x + 3 = 58$$ $$25x + 8 = 58$$ $$25x = 50$$ $$x = 2$$ Ответ: $$x = 2$$