Which of the following functions gives the length of the base edge

a = sqrt(3v/8) which is the first choice

Explanation:
The volume of the right square pyramid is calculated using the following rule:
V = (1/3)*h*a^2 where:
V is the volume
a is the length of the base
h is the height
We are given that the height = 8 in and volume = v, this means that:
v = (1/3)*8*a^2 = (8/3)*a^2

Now, we will solve this equation for a as follows:
v = (8/3)*a^2
3v = 8a^2
3v/8 = a^2
a = sqrt(3v/8) which is the first choice

Hope this helps :)

6(2x + 5y)6 (2x) = 12x6 (5y) = 30y12x + 30y