A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • 5 years ago

x^2+y=120 find y. what is the max area? (the problem is this: a rectangle and a fence to cover 3 sides, find area of the longest side.)

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

    Is the Perimeter = 120?

  2. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    WELL THE FENCING NEED FOR 3 SIDES IS 120

  3. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    o.k. then 2x + y = 120 because two of the sides are the same, 2x, and the other side doesn't have to be, y. so using this equation you get y = 120 - 2x Area = Length * Width = y * x = (120 - 2x)*x That is A = 120x - 2x^2 or prettier: \[A = 120x -2x^2\] This is an upside down parabola so the maximum will be at the vertex. When you find the x value of the vertex, plug it into the equation \[A = 120x -2x^2\] to get the maximum area Does that help?

  4. 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...

23

  • 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.