Q. The area of a rectangular bathroom mirror is 20 square feet. The perimeter is 24 feet. What are the dimensions of the mirror?___ feet by ___ feet
Area Equation: Let's denote the length of the mirror as L feet and the width as W feet. We know that the area (A) of a rectangle is given by the formula A=L×W. We are given that the area is 20 square feet.So, we have the equation:L×W=20
Perimeter Equation: We also know that the perimeter P of a rectangle is given by the formula P=2×(L+W). We are given that the perimeter is 24 feet.So, we have the equation:2×(L+W)=24
Simplify Perimeter: Let's simplify the perimeter equation to express one variable in terms of the other. We can divide both sides of the perimeter equation by 2 to get:L+W=12
Express Width in Terms of Length: Now, we can express W in terms of L using the perimeter equation:W=12−L
Substitute Width into Area Equation: We can substitute W from the perimeter equation into the area equation to find L: L×(12−L)=20 Expanding this, we get: 12L−L2=20
Rearrange Quadratic Equation: To solve for L, we need to rearrange the equation into a standard quadratic form:L2−12L+20=0
Factor Quadratic Equation: Now, we can factor the quadratic equation: L - \(10)(L - 2) = 0\
Solve for Length: Setting each factor equal to zero gives us the possible values for L:L−10=0 or L−2=0So, L=10 or L=2
Calculate Width: If L=10, then W=12−L=12−10=2. If L=2, then W=12−L=12−2=10. Since a rectangle's dimensions are interchangeable, we have two possible sets of dimensions for the mirror: 10 feet by 2 feet or 2 feet by 10 feet.
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