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.
