Answer:
5 inches
Explanation:
The volume is basically
Volume = area of base * height
For pyramid, that area would be

Since, this is square pyramid, the base is a square with side length b, so the area would be

Let height be h
Thus, we can write the formula for volume of square pyramid as:
Volume =

Where
b is side length of base square
h is height of pyramid
Now, given h = 3 and v = 25, we need to find b. let's substitute and figure it out using the formula:

Hence
the side length of the base of the square pyramid is 5 inches