Math equations?

Question

^3sqrt of negative
8
--
27

I had to write this equation this way b/c it wasnt letting me set it up right it is supposed to be ^3sqrt of (-) 8/27

also

I have to find the perimeter of a triangle using these three equations

1. 4

2. sqrt5 - sqrt3

3. sqrt5 + sqrt3


I need to simplify as much as possible . Thank you

Answer 1

a)-2/3
b)assuming these r the lengths of the triangle:
P=4+sqrt5-sqrt3+sqrt5+sqrt3
=4+2sqrt5