Answer:
√(x - 3) = x - 9
x - 3 = (x - 9)²
x - 3 = x² - 18x + 81
x² - 19x + 84 = 0
(x - 7)(x - 12) = 0
x = 7, 12
√(7 - 3) = 7 - 9 √(12 - 3) = 12 - 9
√4 = -2 √9 = 3
2 ≠ -2 3 = 3
The value x = 7 is an extraneous solution of the equation √(x - 3) = x - 9 because it satisfies the equation x - 3 = (x - 9)² and does not satisfy the original equation,
√(x - 3) = x - 9.
