Types of Quadrilaterals
There are six basic types of quadrilaterals:
1. Rectangle
Opposite sides of a rectangle are parallel and equal. All angles are 90º.
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2. Square
Opposite sides of a square are parallel and all sides are equal. All angles are 90º.
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3. Parallelogram
Opposite sides of a parallelogram are parallel and equal. Opposite angles are equal.
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4. Rhombus
All sides of a rhombus are equal and opposite sides are parallel. Opposite angles of a rhombus are equal. The diagonals of a rhombus bisect each other at right angles.
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5. Trapezium
A trapezium has one pair of opposite sides parallel. A regular trapezium has non-parallel sides equal and its base angles are equal, as shown in the following diagram.
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6. Kite
Two pairs of adjacent sides of a kite are equal, and one pair of opposite angles are equal. Diagonals intersect at right angles. One diagonal is bisected by the other.
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