Parallelogram
(Jump to Area of a Parallelogram or Perimeter of a Parallelogram)
A Parallelogram is a flat shape with opposite sides parallel and equal in length.
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Opposite sides are parallel |
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Opposite sides are equal in length |
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Opposite angles are equal (angles "a" are the same, and angles "b" are the same) |
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Angles "a" and "b" add up to 180°, so they are supplementary angles. |
Play with a Parallelogram:
NOTE: Squares, Rectangles and Rhombuses are all Parallelograms!
Example:
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A parallelogram where angles "a" and "b" are right angles is a rectangle! |
Area of a Parallelogram
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The Area is the base times the height: Area = b × h (h is at right angles to b) |
Example: A parallelogram has a base of 6 m and is 3 m high, what is its Area?
Area = 6 m × 3 m = 18 m2
Perimeter of a Parallelogram
The Perimeter is the distance around the edges.
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The Perimeter is 2 times the (base + side length): Perimeter = 2(b+s) |
Example: A parallelogram has a base of 12 cm and a side length of 6 cm, what is its Perimeter?
Perimeter = 2 × (12 cm + 6 cm) = 2 × 18 cm = 36 cm
Diagonals of a Parallelogram
The diagonals of a parallelogram bisect each other.
In other words the diagonals intersect each other at the half-way point.