Algebra/Square Root is Positive

Algebra

Squire Root is Positive

We often say that $\sqrt{x}$ is the positive number, which when squared is equal to x. If x > 0 this is perfectly correct, but if x = 0 then $\sqrt{x} = \sqrt{0} = 0$ which is not positive. So to be technically correct (which is part of the fun of math) we should say that $\sqrt{x}$ is the non-negative number, which when squared is equal to x.

If it is needed to express that a square root may be both positive and negative, you will see $\plusmn \sqrt{x}$.