Question

When you take the fourth root of something, do you have to put + or - signs like when you do square root?

Answer 1

Yes

Answer 2

Yes. because,
16 can be made up from '-2' raised to 4 as well as '2' raised to 4.

Answer 3

(as an example)

Answer 4

Yes.
Think of it as a square root of the square. And then the square root of that. So yes the signs DO matter.