Post a New Question

math

posted by .

a gardener is planning to make a rectangular garden with an area of 80ft^2.she has 12 yards of fencing to put around the perimeter of the garden.what should the dimension of the garden be ?

  • math -

    For a given perimeter, that largest area area of a rectangle is obtained when the rectangle is a square.
    so if each side is x ft
    x^2 = 80
    x = √80 = 4√5

    She needs 16√5 ft or appr 35.8 ft of fencing.
    With only 12 feet she cannot have a rectangular field of 80 ft

    or

    with 12 ft of fencing , she can build a 3by3 square which will hold 9 square ft, not the 80 she wants.

    Your question is flawed.

  • math -- oops -

    She has 12 yards, or 36 feet of fencing.
    That will enclose 9x9 = 81 ft^2, so by moving away from a square, she can use the whole 36 ft to enclose only 80 ft^2.

    80 = 16*5 = 4*(4*5) so if the garden is 8x10 feet, its perimeter is 36 and its area is 80

  • Thanks Steve - math -

    I violated one of the first rules I taught my students years ago ...

    Read the question carefully, and read it more than once.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

More Related Questions

Post a New Question