Respuesta :

Answer:

3

Step-by-step explanation:

[tex] \sf \sqrt{x + 3 = 12} [/tex]

[tex] \sf = \sqrt{x = 12 - 3} [/tex]

[tex] \sf = \sqrt{x = 9} [/tex]

[tex] \sf = \sqrt{9} [/tex]

[tex] \sf = \sqrt{3 \times 3} [/tex]

= 3

Answer:

x = 81

Step-by-step explanation:

Combine like terms:  √x+3=12 becomes √x+3- 3= 12 - 3, or √x = 9.

Square both sides to obtain x:  x = 81