Illustrative Mathematics
Area of a Trapezoid
Here is a straightforward example of how to apply the Pythagorean Theorem to find an unknown side-length of a trapezoid. Commentary gives additional information on proving that the inside of the trapezoid is a rectangle, but is...
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Cut - Stretch - Fold
Students work on determining the area of a tangram piece without using a formula by working with geoboards, graph paper, and tangram pieces. After completing the activity, they apply their experience to determining a formula for finding...
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Geometry Practice: Area of Polygons #9
In this area of polygons worksheet, young scholars find the area of 12 polygons. Each shape is drawn on a grid. The area of each square on the grid is given. Problems are all multiple choice.
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Area is Always Flat, But It's Not Always Regular
Students calculate the area of regular and irregular polygons by counting the number of whole an half squares within the polygon. They determine the formula for regular polygons and label the area in square units.
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Geometry Worksheet
In this geometry learning exercise, learners find the area of four polygons. They compute the measure of an angle. Students find the length of the sides of a right triangle. They name one arc and find the measure of two arcs.