Respuesta :

In the middle part, you have x + 4.
You want x alone, so subtract 4 from each of the 3 parts.

[tex] -3 \le x + 4 \le 13 [/tex]

[tex] -3 - 4 \le x + 4 - 4 \le 13 - 4 [/tex]

[tex] -7 \le x \le 9 [/tex]

[tex] x \ge -7 [/tex]   and   [tex] x \le 9 [/tex]