What is the principal square root of 16

Answer

4

Explanation

The square root of a number always gives two results. One negative and the other one positive.

√16 = - 4 also √16 = + 4.

This is true because,

(-4) ² = 16 and

(+4) ² = 16.

When we are looking for the square root if a positive number we are actually interested with the positive root. This is the one referred to as principal square root.

∴ The principal square root of 16 is 4.