Unit+3+-+Lesson+1+-+Perimeter+-+The+Distance+around+a+Polygon

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The ExploreLearning: Rectangle - Perimeter and Area Gizmo is a simple, but powerful tool that can be used in many ways. Options are available to manipulate the side length of either a square or a rectangle using the slider provided. The user can choose to reveal the perimeter or area of the shape, based on the length of the sides; or they can activate the rulers, and measure each side, and use the formulas they know for calculating the perimeter.======

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The Shodor Interactive: Perimeter Explorer is a manipulative that allows the user to generate a random geometric shape with a defined area, and solve for the perimeter. The user can define whether they would like to have a rectangular or non-rectangular shape displayed. The applet also has the ability to outline the shape to offer visual support and to create a boundary.======