Interactive
Geometry Dictionary
How Do You Find the Area of a Parallelogram? In a parallelogram,
opposite sides are parallel and have the same length. This applet will show you how to find the area of a parallelogram
if you already know how to find the area of a rectangle. You can cut up the
parallelogram into pieces, put them together to find a rectangle, and
then use the formula for the area of a rectangle.
Drag vertex A of the parallelogram to change it to a rectangle. What is the area of
the rectangle that you get? What measurements of the parallelogram do
you need in order to find its area?
You can drag vertex C to change the size and shape of the parallelogram. Click the boxes to show
a rectangle that can be made from the parallelogram, show the dimensions of the parallelogram, or to start over.
Do all the parallelograms have the same area?
Answer:
By dragging point A to the location of point D,
you can change the parallelogram into a rectangle with the same base and
height as the parallelogram. The area of the rectangle is the base of
the parallelogram times its height. Thus, you just need to measure the base
and height of a parallelogram to be able to compute its area.
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Area of a parallelogram
= base times height
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Use what you know about the area of a parallelogram to find the area
of a triangle. | 
Pre-K - 2 
