Q. A rectangular rug has an area of 21square feet. Its perimeter is 20feet. What are the dimensions of the rug?____ feet by ____ feet
Define Rug Area: Let's denote the length of the rug as l feet and the width as w feet. The area of the rug is given by the product of its length and width.Which equation represents the area of a rectangle.Area = l×w
Calculate Area: The area of the rectangular rug is given as 21 square feet.Which equation represents the area of this rectangular rug.Substitute 21 for Area in Area=l×w.21=l×w
Define Perimeter: The perimeter of a rectangle is given by the sum of twice its length and twice its width.Which equation represents the perimeter of a rectangle.Perimeter = 2l+2w
Calculate Perimeter: The perimeter of the rug is given as 20 feet.Which equation represents the perimeter of this rectangular rug.Substitute 20 for Perimeter in Perimeter=2l+2w.20=2l+2w
Simplify Perimeter Equation: Let's simplify equation (2) by dividing all terms by 2 to make the calculations easier.220=2(2l+2w)10=l+wNow we have a simpler equation:10=l+w (3)
Express Width in Terms of Length: We can express w from equation (3) in terms of l.w=10−lNow we can substitute this expression for w into equation (1).
Substitute Width into Area Equation: Substitute w=10−l into 21=l×w.21=l×(10−l)This gives us a quadratic equation:21=10l−l2
Rearrange Quadratic Equation: Rearrange the quadratic equation to standard form.0=l2−10l+21
Factor Quadratic Equation: Factor the quadratic equation. (l−7)(l−3)=0
Solve for Length: Set each factor equal to zero and solve for l.l−7=0 or l−3=0This gives us two possible solutions for l:l=7 or l=3
Find Possible Dimensions: If l=7, then from equation (3) w=10−l, we get w=10−7=3. If l=3, then w=10−3=7. So the dimensions of the rug can be either 7 feet by 3 feet or 3 feet by 7 feet.
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