Решите уравнение: 15 х^2 - (5 х+2) (3 х-4) = 1

15 * х^2 - (5 * х + 2) * (3 * х - 4) = 1;

Раскроем скобки.

15 * x^2 - (5 * x * 3 * x - 4 * 5 * x + 2 * 3 * x - 2 * 4) = 1;

15 * x^2 - (15 * x^2 - 20 * x + 6 * x - 8) = 1;

15 * x^2 - (15 * x^2 - 14 * x - 8) = 1;

15 * x^2 - 15 * x^2 + 14 * x + 8 = 1;

x^2 * (15 - 15) + 14 * x + 8 = 1;

x^2 * 0 + 14 * x + 8 = 1;

14 * x + 8 = 1;

14 * x = 1 - 8;

14 * x = - 7;

x = - 7/14;

x = - 7 / (7 * 2);

x = - 1 / (1 * 2);

x = - 1/2;

x = - 0.5;

Ответ: х = - 0,5.