Quadratic equations

posted by .

Building a rectangular room with fixed perimeter of 280ft
what dimentions would yield the maximum area?
What dimentions would yeild the minimum area?

  • Quadratic equations -

    A rectangle of largest area is a square.
    So divide your perimeter by 4.

    To build a room of minimum area is a rather silly question.

  • Quadratic equations -

    I apologize for my silly question. I followed your advice, revised my question and found my answer. Thank you.

  • Quadratic equations -

    x = length
    y = width
    A = x y
    x+y=140
    A = x(140-x)
    A = 140 x - x^2
    look at shape of parabola by completing the square
    x^2 -140 x = -A
    x^2 - 140 x + 4900 = -A + 4900
    (x-70)^2 = -A + 4900
    the vertex will be at x = 70 and A = 4900 and the -A means that the parabola opens down (sheds water) so that vertex is the maximum where x = y =70 as Reiny told you.
    since a negative x or y does not make much sense, the area may not get any smaller than zero when x --> 0 or y -->0 0

  • Math 9 -

    Wasn't very helpful.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. calculus

    A farmer has 180 feet of fence and wants a pen to adjoin to the whole side of the 120 foot barn as shown. What should the dimentions be for maximum area. Note that in this case Write the equation for perimeter of the three sided rectangle. …
  2. math

    if you have to build a pool of 72 yards in your yard,and the construction company wants you to choose the dimentions (lenth and width) of the pool.how do you choose the dimentions that will give you the greatest area possible?
  3. Algebra

    A carpenter is building a rectangular room with a fixed perimeter of 112 ft. What dimensions would yield the maximum area?
  4. College Algebra

    Translate the problem into a pair of linear equations in two variables. Solve the equations using either elimination or substitution. State your answer for both variables. The perimeter of a rectangle is 72m. If the width were doubled …
  5. college Algebra

    This is my problem: A carpenter is building a rectangular room with a fixed perimeter of 336 ft. What dimensions would yield the maximum area?
  6. math

    If the numerical values of the perimeter and the area of a square are equal, what are the dimentions of the square?
  7. MATH

    FIND THE PERIMETER AND AREA OF A ROOM WITH THESE DIMENTIONS 11FT 13FT 14FT 3FT
  8. Algebra 2

    A rancher is fencing off a rectangular area with a fixed perimeter of 76 m. What dimensions would yield the maximum area?
  9. math 12

    A)a shed, in the shape of a square based prism, is to have volume 800meters cubed. determin the dimentions of the shed, with the minimum surface area. B)how would the answer change if the minimum surface area did not include the bottem …
  10. calculus

    from a cardboard box 12 in by 8 inches are cut out so the sides can be folded up to make a box . What dimentions will yield a maximum volume?

More Similar Questions