A quadrilateral is a plane shape that has four (4) sides. Quadrilaterals include:

1. Rectangles
2. Squares
3. Parallelograms
4. Rhombuses
5. Trapeziums
6. Kites

1. Rectangles
2. The opposite sides are equal in length
3. The opposite sides are parallel
4. All angles are equal. Each angle is equal to 90o (i.e. right angles)
5. The two diagonals are equal in length
6. They have 2 (two) lines of symmetry
7. The diagonals bisect each other

1. Squares
2. Each interior angle is equal t 90o
3. All sides are equal in length
4. Opposite sides are parallel
5. The diagonals intersect at 90o
6. The diagonals bisect corner angles so that each angle is 45o
7. They have four lines of symmetry
8. The diagonals bisect each other
9. Parallelograms
10. Both pairs of opposite sides are parallel
11. Opposite sides are equal in length
12. Opposite angles are equal in size
13. No line of symmetry
14. The diagonals bisect each other
15. Rhombuses
16. All sides are equal
17. Opposite angles are equal in size
18. Opposite sides are parallel
19. Each diagonal bisect the corner angles
20. Diagonals intersect at 90o
21. The diagonals bisect each other
22. They have two lines of symmetry
23. Trapeziums

A trapezium is a quadrilateral that has one pair of opposite sides parallel. There are two types of trapezium:

1. Isosceles trapezium
2. Non-isosceles trapezium

Isosceles trapezium

1. One pair of opposite sides is parallel
2. The parallel sides are not equal in length
• They have two pairs of equal angles
1. They have equal diagonals
2. They have one line of symmetry
3. The non-parallel opposite sides are equal in length.

Non-isosceles trapezium

1. One pair of opposite sides is parallel
2. No line of symmetry
3. Kites
4. The adjacent pairs of sides are equal in length
5. One pair of opposite angle is equal in size
6. Diagonals intersect at right angle (90o)
7. One diagonal bisects the other diagonal
8. They have one line of symmetry