Answer:
(8x-9)(8x+9)
Step-by-step explanation:
64x^2 - 81
Rewriting
(8x)^2 - 9^2
We recognize that this is the difference of squares
a^2 - b^2 = (a-b)(a+b)
(8x+9)(8x-9)
64x^2= 8x*8x
-81= 9*-9
