12x² - (4x - 3)(3x + 1) = -2
12x² - (12x² - 9x + 4x - 3) = -2
12x² - 12x² + 5x + 3 = -2
5x + 3 = -2
5x = -5
x = -1
ответ: {-1}
12x² - (4x - 3)(3x + 1) = -2
12x² - (12x² - 9x + 4x - 3) = -2
12x² - 12x² + 5x + 3 = -2
5x + 3 = -2
5x = -5
x = -1
ответ: {-1}