Question
upstudy study bank question image url

Catarina and Tom want to buy a rug for a room that is 11 by 20 feet. They want to leave an even strip of flooring uncovered around the edges of the room. How wide a strip will they have if they buy a rug with an area of 112 square feet? They will have a \( \square \mathrm{ft} \) wide strip of flooring uncovered.

Ask by Gough Cox. in the United States
Mar 11,2025

Upstudy AI Solution

Tutor-Verified Answer

Answer

They will have a 2 ft wide strip of flooring uncovered.

Solution

Let \( x \) be the width of the uncovered strip. Then the rug will cover an area that is reduced by \( 2x \) in each dimension, so the dimensions of the rug will be: \[ 11 - 2x \quad \text{and} \quad 20 - 2x \] Since the rug's area is \( 112 \) square feet, we have: \[ (11-2x)(20-2x) = 112 \] First, expand the left-hand side: \[ (11-2x)(20-2x) = 220 - 22x - 40x + 4x^2 = 220 - 62x + 4x^2 \] Setting up the equation: \[ 4x^2 - 62x + 220 = 112 \] Subtract \( 112 \) from both sides: \[ 4x^2 - 62x + 108 = 0 \] Divide the equation by \( 2 \) for simplicity: \[ 2x^2 - 31x + 54 = 0 \] Now, we solve the quadratic equation using the quadratic formula: \[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] Here, \( a = 2 \), \( b = -31 \), and \( c = 54 \). Compute the discriminant: \[ b^2 - 4ac = (-31)^2 - 4(2)(54) = 961 - 432 = 529 \] Since \( 529 = 23^2 \), the solutions are: \[ x = \frac{31 \pm 23}{4} \] This gives two possible values: \[ x = \frac{31 + 23}{4} = \frac{54}{4} = 13.5 \] \[ x = \frac{31 - 23}{4} = \frac{8}{4} = 2 \] The value \( x = 13.5 \) feet is not feasible because subtracting \( 2x \) from the room's dimensions would yield negative values. Therefore, the only valid solution is: \[ x = 2 \] Thus, they will have a \( \boxed{2 \text{ ft}} \) wide strip of flooring uncovered.

Answered by UpStudy AI and reviewed by a Professional Tutor

error msg
Explain
Simplify this solution

Mind Expander

To find the width of the strip of flooring that will remain uncovered, we first need to determine the dimensions of the rug and the total area of the room. The room is 11 by 20 feet, giving a total area of: \[ 11 \times 20 = 220 \text{ square feet} \] Catarina and Tom want a rug with an area of 112 square feet. The area of the uncovered strip can be found by subtracting the area of the rug from the area of the room: \[ 220 \text{ square feet} - 112 \text{ square feet} = 108 \text{ square feet} \] Now, if we let \( x \) be the width of the strip on each side, the dimensions of the rug can be represented as: Width of rug = \( 11 - 2x \) Length of rug = \( 20 - 2x \) Hence, the area of the rug is: \[ (11 - 2x)(20 - 2x) = 112 \] Now, we can set up the equation: \[ 220 - 62x + 4x^2 = 112 \] Rearranging gives: \[ 4x^2 - 62x + 108 = 0 \] This can be solved using the quadratic formula: \[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] Plugging in \( a = 4 \), \( b = -62 \), and \( c = 108 \): \[ x = \frac{62 \pm \sqrt{(-62)^2 - 4 \cdot 4 \cdot 108}}{2 \cdot 4} \] Calculating further leads to: \[ x = \frac{62 \pm \sqrt{3844 - 1728}}{8} \] \[ x = \frac{62 \pm \sqrt{2116}}{8} \] \[ x = \frac{62 \pm 46}{8} \] This gives two possible solutions for \( x \): 1. \( x = \frac{108}{8} = 13.5 \) (not possible since it's wider than the room) 2. \( x = \frac{16}{8} = 2\) Thus, the width of the strip of flooring uncovered will be \( \boxed{2} \) feet.

Related Questions

Latest Geometry Questions

Try Premium now!
Try Premium and ask Thoth AI unlimited math questions now!
Maybe later Go Premium
Study can be a real struggle
Why not UpStudy it?
Select your plan below
Premium

You can enjoy

Start now
  • Step-by-step explanations
  • 24/7 expert live tutors
  • Unlimited number of questions
  • No interruptions
  • Full access to Answer and Solution
  • Full Access to PDF Chat, UpStudy Chat, Browsing Chat
Basic

Totally free but limited

  • Limited Solution
Welcome to UpStudy!
Please sign in to continue the Thoth AI Chat journey
Continue with Email
Or continue with
By clicking “Sign in”, you agree to our Terms of Use & Privacy Policy