Square roots are always nonnegative

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Square roots are always nonnegative

Many people around the world get confused, thinking that $x^2 = 16$ and $x= \sqrt{16}$ are the same. Though both of these are similar, one of them only has one answer. If we take $x^2 = 16$, we can see that it has $2$ answers; $4$ and $-4$. On the other hand, $x = \sqrt{16}$ only has one.


Square Root is a function, and a function cannot have two different answers for one input. Technically $-4$ and $4$ are "square roots" of $16$, but the square root function only represents one of them--the nonnegative answer.