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## Area Tool

6-8
Standards:
Math Content:
Geometry

Use this tool to determine how the length of the base and the height of a figure can be used to determine its area. Can you find the similarities and differences between the area formulas for trapezoids, parallelograms, and triangles?

• Modes: Investigate trapezoids, parallelograms, and triangles, using the tabs along the top of the frame. Drag the vertices to explore different sizes of each shape.
• The Add to Table button can be used to record data in the table, which may be useful in trying to identify patterns.
• The lock button, located at the lower right-hand corner of the interactive, will lock and unlock the height of the polygon. This may be useful in finding the formula for a polygon's area.
Investigate various sizes for each of the different shapes.
• What is the formula for finding the area of a trapezoid? How is the length of the mid-line involved in the formula?
• What is the formula for finding the area of a parallelogram? How is it related to the formula for finding the area of a rectangle?
• What is the formula for finding the area of a triangle? How is it related to the formula for finding the area of a rectangle?