Algebra square root question

 I learned this in 8th grade, but that was two years ago. i think that -+ means that it was a positive or negative to get the answer. 

I am not sure where you are getting the +- from.

If you do this logically, you would take the square of 16, and then + 1.

This will give you x = 5. You don't 'quantify' that the +- should be there. It is not needed. Typically it is seen in polynomials and the quadratic formula.

You can't have anything but x = 5.