Respuesta :

Answer:

f(y)= y²-8y+16

Step-by-step explanation:

we are looking for f(y) which basically means x, (inverse)

step1            y=x^1/2+4

       2          x^1/2=y-4

      3          √x=y-4    / square both sides

      4           x = y²-8y+16

  *note      x presents f(y)