Respuesta :

sqdancefan

Answer:

  y ≈ 17.32

Step-by-step explanation:

The triangles are all similar, so you have ...

  long-side/hypotenuse = y/(5+15) = 15/y

Cross-multiplying gives ...

  y^2 = 15·20 = 300 . . . . . . . . take the square root to find y

  y = √300 = 10√3 ≈ 17.32