You can put this solution on YOUR website! (64/81) to the negative 3/4 exponent simplifies to what and factors to what
----
(64/81)^(-3/4)
----
The negative in the exponent means "invert".
The 3 means to "cube"
The 4 means take the "4th root".
----
These instruction can be performed in any order.
---
If you take the 4th root 1st you get:
(2/3)^(-3)
---
If you invert next you get:
(3/2)^(3)
---
If you then cube the base youo get:
= 27/8
============
Cheers,
Stan H.
=================