Simple notation question about brackets

Question

Is this notation correct? I am not sure about the brackets.

$x^2=4$

$x=\{-2,2\}$

Thanks in advance.

Answer 1

What you need to denote is $$x \in \{-2, 2\}$$

That is, you want to convey that $x$ is an element of the solution set $\{-2, 2\}$. $x$ is not equal to the set.

So simply replace the symbol "$=$" with the symbol "$\in$", and all is then good.