How to find area in square root 400

The square root of 400 is 20, because 20 times 20 is 400.

How do you find the square root of 400?
To start finding a square root via prime factorization, first, try to reduce your number into its perfect square factors.
We want to find the square root of 400. To begin, we would divide the number into perfect square factors. ... We would write this as:
Sqrt(400) = Sqrt(25 × 16)