A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing


  • 5 years ago

A. A rectangular garden with perimeter 40m is to be fenced. 1- What are dimensions of a garden and its maximum area? 2-what are the dimensions of a rectangle with area 45m square. and the minimum perimeter?

  • This Question is Closed
  1. dumbcow
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Perimeter of rectangle is 2L + 2w : where L,w are length and width Area is L*w ok so 2L + 2w = 40 and we need to maximize area This means define Area as a function of one variable, take derivative and set it equal to zero. Lets solve for L -> L = (40-2w)/2 = 20 - w Now substitute (20-w) in for L in Area formula ->A = (20-w)*w = 20w - w^2 Differentiate using power rule ->dA/dw = 20 - 2w set =0 and solve -> 20-2w = 0 -> 2w=20 -> w =10 Now plug that value in for w in our perimeter formula and solve for L ->2L + 2(10) = 40 -> 2L = 20 -> L = 10 So L=w=10 and area = 10*10=100 Hope this helps

  2. Not the answer you are looking for?
    Search for more explanations.

    • Attachments:

Ask your own question

Sign Up
Find more explanations on OpenStudy
Privacy Policy

Your question is ready. Sign up for free to start getting answers.

spraguer (Moderator)
5 → View Detailed Profile

is replying to Can someone tell me what button the professor is hitting...


  • Teamwork 19 Teammate
  • Problem Solving 19 Hero
  • You have blocked this person.
  • ✔ You're a fan Checking fan status...

Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.

This is the testimonial you wrote.
You haven't written a testimonial for Owlfred.