Answer:
B
Step-by-step explanation:
Substitute x = 5 and x = 9 into f(x) and equate
f(5) = (5 - b)² = 25 - 10b + b²
f(9) = (9 - b)² = 81 - 18b + b²
Then equating the 2 gives
b² - 10b + 25 = b² - 18b + 81 ( subtract b² - 18b from both sides )
8b + 25 = 81 ( subtract 25 from both sides )
8b = 56 ( divide both sides by 8 )
b = 7
Then
f(x) = (x - 7)² and
f(1) = (1 - 7)² = (- 6)² = 36 → B
÷ 
= 