Х^3-х^2-16х+16 can be factored as (x-4)(x-2)^2

64b^2-(8-b)^2 can be factored as (8b+(8-b))(8b-(8-b)) = (8b+8-b)(8b-8+b) = (9b)(7b) = 63b^2

Final answer: (x-4)(x-2)^2 and 63b^2