Question

How come when you square root a number, like for example 9, its + and - 3

Answer 1

let x=sqrt(9)
or xsquaring both sides we have
x^2=9
x^2-9=0
x^2 -(3)^2=0
(x+3)(x-3)=0 (factorising)
thus either x+3=0(means x=-3) or x-3=0(meansx=3)
hence x=+3 or -3

Answer 2

Thank you :) I get it now!

Answer 3

WELCOME

Answer 4

A small note about square roots:
The symbol \(\sqrt{~~}\) (the radical sign) is only defined as the principal/positive square root.
All nonnegative real numbers have two square roots: \(\pm \sqrt{N} \to \sqrt{N} \text{ and } \neg \sqrt{N} \).

Sometimes there is confusion in the symbol and the actual term "square root."