Answer:
(x - 8)² = 38
Explanation:
Given
x² - 16x + 26 = 0 ( subtract 26 from both sides )
x² - 16x = - 26
Using the method of completing the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(- 8)x + 64 = - 26 + 64
(x - 8)² = 38 ← as required