Respuesta :

y = x^2
80 = x^2
x = √80
x = 8.94

Answer:

x = 64

Step-by-step explanation:

Given y is directly proportional to [tex]\sqrt{x}[/tex] then the equation relating them is

y = k[tex]\sqrt{x}[/tex] ← k is the constant of proportion

To find k use the condition y = 60 when x = 36, then

60 = k [tex]\sqrt{36}[/tex] = 6k ( divide both sides by 6 )

10 = k

y = 10[tex]\sqrt{x}[/tex] ← equation of proportion

When y = 80 , then

80 = 10[tex]\sqrt{x}[/tex] ( divide both sides by 10 )

8 = [tex]\sqrt{x}[/tex] ( square both sides )

64 = x