Respuesta :

altavistard

Answer:

16

Step-by-step explanation:

Start by adding 9 to both sides, obtaining:  √(x + 9) = 5.

Square both sides, obtaining:   x + 9 = 25.

Subtract 9 from both sides:  x = 16

Note that √(16+9) - 9 = -4, as required.