Geometry

posted by .

The area of a 300' by 400' rectangle is doubled by adding a strip of width around the perimeter. Approximately how wide is that strip?

  • Geometry -

    old area = 300*400 = 120 000
    new area = 240 000

    (300+2x)(400+2x) = 240000
    120000+1400x + 4x^2 = 240000
    simplify and divide by 4.

    x^2 + 350x - 30000 = 0
    x = (-350 ± √242500)/2
    = appr 71.22 or some negative which we will reject

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. math

    A rectangular skating rink measuring 30m by 20m is doubled in area by adding a strip at one end of the rink and a strip fo the same width along one side of the rink. Find the width of the strips if the enlarged rink is still rectangular.
  2. algebra 2

    Farmer Brown wants to double the size of his rectangular backyard vegetable patch by adding a strip (of the same width) all the way around it. If its current patch is 12 feet by 18 feet, how wide does the strip need to be?
  3. algebra 2

    Farmer Brown wants to double the size of his rectangular backyard vegetable patch by adding a strip (of the same width) all the way around it. If its current patch is 12 feet by 18 feet, how wide does the strip need to be?
  4. alg 2

    A rectangular plot is 30 feet long and 20 feet wide. The area will be doubled by adding a strip at one end and another strip of the same width on one side. What would be the width of the strip?
  5. Grade 9 Algebra

    4. WALLPAPER A decorative wallpaper strip has an area of 50 + 20r. If the width of the strip is 5 inches, what expression represents the length of the strip?
  6. Math

    A rectangular lawn is 60meters by 80meters. A part of the lawn is torn out to install a pool, leaving a strip of lawn of uniform width around the pool. The area of the poolnis 1/6 of the old lawn area. How wide is the strip of lawn?
  7. Mensuration

    A sheet of paper measures 30cm by 20cm. A strip 4cm wide is cut from it all around. Find the area of the remaining sheet and also the area of the strip cut out.
  8. math

    A sheet of paper measures 50 CM by 30cm. A strip 6 CM wide is cut from all around. Find the area of the remaining sheet and also the area of the strip cut out.
  9. Math

    A sheet of paper measures 30 cm by 2 cm. A strip 5 cm wide is cut from it all around. Find the area of the remaining sheet and the strip cut out.
  10. Maths

    A sheet of paper measuring 30cm by 20cm . A strip of Wide 4cm cut from it all around. Find the área of the remaining sheet and also the área of the cut strip

More Similar Questions