Question

Max/min question grade 10...just cheking answers

Answer 1

A lifeguard marks off a rectangular swimming area at a beach with 200m of rope. What is the greatest area of water she can enclose?

Answer 2

I got 2,500....but the answer sheet says 5,000! Which one is right?

Answer 3

Please?

Answer 4

Perimiter=P
P=2(l+w)
wait, do we have to use calculus?

Answer 5

Perimiter=P
P=2(L+w)=200
100=L+w
L=100-w

Area is maximized when the derivative is zero:
A=wL=w(100-w)=100w-w^2
A'=0=100-2w
w=50

from earlier we have

L=100-w=100-50=50

so the greatest possible area is

A=wL=(50)(50)=2500

Answer 6

Yep your sheet is wrong, I'd bet on it.

Answer 7

Thanks so much