I think this answer is right but not 100% sure, 5 Root of 15 + 3
First you subtract 25 from 5 which equals 20 then you multipliy 4 to 20 and you get 80...so 80 is your solution.
Answer:

Step-by-step explanation:
we know that
The volume of a trough is equal to

where
B is the area of equilateral triangle
L is the length of a trough
step 1
Find the area of equilateral triangle B
The area of a equilateral triangle applying the law of sines is equal to

where


substitute


step 2
Find the volume of a trough

we have


substitute

