Answer:
(a - b - 5)(a - b + 5)
Step-by-step explanation:
(a - b)² = a² + b² - 2ab
Given
a² + b² - 2ab - 25
= (a - b)² - 25 ← this is a difference of squares and factors in general as
a² - b² = (a - b)(a + b) , then
(a - b)² - 25
= (a - b)² - 5²
with a = a - b and b = 5 , so
(a - b)² - 5²
= (a - b - 5)(a - b + 5)
