Question

Factor.

49x^16−16y^64

(7x^4−4y^8)(7x^4+4y^8)

(7x^8−4y^32)^2

(7x^8−4y^32)(7x^8+4y^32)

(7x^4−4y^8)^2

Answer 1

its D
(7x^4-4y^8)^2 and yea 

Answer 2

This was the correct answer, I even provided proof from my own test. Hope this helps!