(4x - 9)(x + 3) - (x - 7) = 5(x - 3)(x + 3)
4x^2 + 12x - 9x - 27 - (x - 7) = 5(x^2 - 9)
4x^2 + 3x - 27 - x + 7 = 5x^2 - 45
4x^2 + 2x - 20 = 5x^2 - 45
2x = 25
x = 12.5
Ответ: x = 12.5.
(4x - 9)(x + 3) - (x - 7) = 5(x - 3)(x + 3)
4x^2 + 12x - 9x - 27 - (x - 7) = 5(x^2 - 9)
4x^2 + 3x - 27 - x + 7 = 5x^2 - 45
Упростим полученное уравнение:4x^2 + 2x - 20 = 5x^2 - 45
2x = 25
x = 12.5
Ответ: x = 12.5.