Respuesta :
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