Solve by completing the square: x^2 - 8x + 12 = 0

x² - 8x + 12 = 0 (x - 4)² - 16 + 12 = 0 (x - 4)² - 4 = 0 (x - 4)² = 4 x - 4 = +- 2 x = 6 x = 2