Respuesta :

Banabanana
The altitude to the hypotenuse of a right triangle is the mean proportional between the segments into which it divides the hypotenuse ⇒

altitude = √(9*3) = √27

By the Pythagorean theorem:

y = √(9² + (√27)²) = √(81+27) = √108 = 6√3  ← answer