The answer here would be x=65.
Let us assume the length of a side of the square floor = x feet
Area of the square floor as given in the question = 320 square feet
Then
x^2 = 320
x^2 = (17.89)^2
Then
x = 17.89
= 18 feet approx
From the above deduction, it can be easily concluded that the correct option among all the options that are given in the question is the second option or option "B".
The answer is y=3(x-1)^2+6
Did the question give you any lengths of the sides?
Answer:

Step-by-step explanation:
La función es

Diferenciando con respecto a
obtenemos

Igualar con cero

Doble derivada de la función

Entonces, la función es máxima cuando el número de unidades vendidas,
,