Respuesta :

Answer:

The answer is 12.4641016151

Step-by-step explanation:

Trust me, I did this on a test before

Answer:

The number is 69.

Step-by-step explanation:

[tex]\sqrt{(x+12)} =9[/tex]

Square both sides.

[tex]x+12=81[/tex]

Solve for x. Subtract 12 from both sides.

[tex]x=81-12\\x=69[/tex]

Check.

[tex]\sqrt{(69+12)} =9\\\sqrt{81} =9[/tex]