Question

What is the square root of 400 and how do you know? ​

Answer 1

The square root of 400 is represented by √400, where ‘√’ represents a radical and a radicand represents its value. It is rational to multiply 400 by 20, which is 20. Simple prime factorization or long division can be used to find the square root. Taking the square root of 400, we get √400 = ±20

Explanation:

Answer 2

The square root of 400 is 20.

This can be found because to find the square root of 400, we need to find a number that multiplies by itself to result in 400. 20 • 20 = 400, so 20 is the square root of 400.

The same rule applies to other squares; numbers must be able to multiply by themselves to result in the square. An example would be 169. The square root of 169 is 13 because 13 • 13 = 169. 14 • 14 = 196, so 14 is the square root of 196. This goes on with an infinity of numbers because any number can be multiplied by itself to receive a square.