Respuesta :

Answer:

x=9

Step-by-step explanation:

Hello!☺

[tex]Answer:\boxed{x=9}[/tex]

[tex]Explanation:[/tex]

[tex]x-21=-12[/tex]

In our first/last step, we will add 21 to both sides:

[tex]x-21+21=-12+21\\x=9[/tex]

[tex]x=9[/tex] is your answer.

Hope this helps!☺