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6th to 8th
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?
: Investigate trapezoids, parallelograms, and triangles, using the tabs along the top of the frame. Drag the vertices to explore different sizes of each shape.
Add to Table
button can be used to record data in the table, which may be useful in trying to identify patterns.
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?
Objectives and Standards
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Geometry / Measurement
Understand that by similarity, side ratios in right triangles are properties of the angles in the triangle, leading to definitions of trigonometric ratios for acute angles.
RT @DuttonA28: @NCTM #100days Look what came in the mail! So excited to start reading. Thanks for the PD sessions. I’ve been inspired & can…
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