Respuesta :

Answer:

Step-by-step explanation:

f(x)=x(50-x)=50x-x²=-(x²-50x+(-50/2)²-(-50/2)²)

=-(x²-50x+625)+625

=(x-25)²+625

area is maximum at x=25 and max. area=625

length=25

and width=50-25=25

or rectangle is a square.