69 - 5(x - 2)² = 24
69 - 5(x² - 4x + 4) = 24
69 - 5x² + 20x - 20 - 24 = 0
- 5x² + 20x +25 = 0
5x² - 20x - 25 = 0
impartim la 5
x² - 4x - 5 = 0
x² + x - 5x - 5 = 0
x(x + 1) - 5(x + 1) = 0
(x + 1)(x - 5) = 0
x + 1 = 0 => x₁ = - 1
x - 5 = 0 => x₂ = 5