what number is equal to $sqrt{16}$?

Explanation:

Step1: Recall square - root definition

The square - root of a number (x), denoted as (\sqrt{x}), is a value (y) such that (y^2=x). We need to find a number (y) where (y^2 = 16). Since (4\times4=16) and ((- 4)\times(-4)=16), the principal square - root of 16 (denoted by (\sqrt{16})) is 4. The symbol (\sqrt{x}) represents the non - negative square root of (x) when (x\geq0).

Answer:

4