Respuesta :

[tex]|a|=a\ if\ a\ \ \textgreater \ 0\\|0|=0\\|a|=-a|\ if\ a \ \textless \ 0\\-------------------------\\|x|=7\ if\ \huge\boxed{x=7\ or\ -7}\to\your\ answer\ \boxed{b.}[/tex]

Answer:

The answer is b

Step-by-step explanation: