A rectangular sticker has an area of 28square centimeters and a perimeter of 22centimeters. What are the dimensions of the sticker?____ centimeters by ____ centimeters
Q. A rectangular sticker has an area of 28square centimeters and a perimeter of 22centimeters. What are the dimensions of the sticker?____ centimeters by ____ centimeters
Define Variables: Let l be the length and w be the width of the rectangle.The area of a rectangle is given by the formula A=l×w.
Area and Perimeter Formulas: The area of the sticker is given as 28 square centimeters.Substitute 28 for A in the formula A=l×w.28=l×w
Substitute Values: The perimeter of a rectangle is given by the formula P=2l+2w.The perimeter of the sticker is given as 22 centimeters.Substitute 22 for P in the formula P=2l+2w.22=2l+2w
Simplify Perimeter: Divide the perimeter equation by 2 to simplify.222=22l+2w11=l+w
Solve System of Equations: We now have a system of two equations with two variables:28=l×w (Area equation)11=l+w (Perimeter equation)We can solve this system by expressing one variable in terms of the other using the perimeter equation and then substituting into the area equation.
Express Width in Terms of Length: Express w in terms of l using the perimeter equation.w=11−l
Substitute Width into Area Equation: Substitute w=11−l into the area equation 28=l×w.28=l×(11−l)
Expand and Rearrange Equation: Expand the equation and move all terms to one side to form a quadratic equation.28=11l−l20=l2−11l+28
Factor Quadratic Equation: Factor the quadratic equation.0=(l−4)(l−7)
Solve for Length: Solve for l by setting each factor equal to zero.l−4=0 or l−7=0l=4 or l=7
Find Possible Dimensions: If l=4, then w=11−l=11−4=7. If l=7, then w=11−l=11−7=4. So the dimensions of the sticker can be either 4cm×7cm or 7cm×4cm.
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