2. • Quadrilaterals means a figure which has more than 4
side.
for example ; Square,
Rectangle….
PROPERTIES
1. Four sided
2. Has four vertices
3. Interior Angles add up to 360°
THERE ARE 2 TYPES OF QUADRILATERALS :
1. REGULAR [ ONLY SQUARE IS REGULAR QUADRILATERAL]
2. IRREGULAR
5. SQUARE
In geometry, a square is a regular quadrilateral, which means that it has
four equal sides and four equal angles (90-degree angles, or right
angles). It can also be defined as a rectangle in which two adjacent sides
have equal length. A square with vertices ABCD would be denoted as
∎ 𝐴𝐵𝐶𝐷
RECTANGLE
In Euclidean plane geometry, a rectangle is a quadrilateral with four right
angles. It can also be defined as an equiangular quadrilateral, since
equiangular means that all of its angles are equal (360°/4 = 90°). It can
also be defined as a parallelogram containing a right angle. A rectangle
with four sides of equal length is a square. The term oblong is occasionally
used to refer to a non-square rectangle. A rectangle with vertices ABCD
would be denoted as Rectangle. ∎ 𝐴𝐵𝐶𝐷
6. RHOMBUS
• In Euclidean geometry, a rhombus(◊), plural rhombi or rhombuses, is a
simple (non-self-intersecting) quadrilateral whose four sides all have the
same length. Another name is equilateral quadrilateral, since equilateral
means that all of its sides are equal in length. The rhombus is often
called a diamond, after the diamonds suit in playing cards which
resembles the projection of an octahedral diamond, or a lozenge, though
the former sometimes refers specifically to a rhombus with a 60° angle ,
and the latter sometimes refers specifically to a rhombus with a 45°
angle.
• Every rhombus is a parallelogram and a kite. A rhombus with right angles
is a square.
7. KITE
A kite is traditionally a tethered heavier-than-air craft with wing surfaces that
react against the air to create lift and drag. A kite consists of wings, tethers,
and anchors. Kites often have a bridle to guide the face of the kite at the
correct angle so the wind can lift it
PARALLELOGRAM
One special kind of polygons is called a parallelogram. It is a quadrilateral
where both pairs of opposite sides are parallel. There are six important
properties of parallelograms to know: Opposite sides are congruent (AB =
DC).
PARALLELOGRA
M
KITE
8. TRAPEZIUM
A trapezoid (called a trapezium in the UK) has a pair of opposite sides parallel.
It is called an Isosceles trapezoid if the sides that aren't parallel are equal in
length and both angles coming from a parallel side are equal, as shown.
ISOSCELES TRAPEZIUM
In Euclidean geometry, an isosceles trapezoid (isosceles trapezium in British
English) is a convex quadrilateral with a line of symmetry bisecting one pair of
opposite sides. It is a special case of a trapezoid. In any isosceles trapezoid
two opposite sides (the bases) are parallel, and the two other sides (the legs)
are of equal length (properties shared with the parallelogram). The diagonals
are also of equal length. The base angles of an isosceles trapezoid are equal in
measure (there are in fact two pairs of equal base angles, where one base
angle is the supplementary angle of a base angle at the other base).
9.
10. SQUARE
A square has equal sides and every angle is a right angle (90°)
Also opposite sides are parallel.
A square also fits the definition of a rectangle (all angles are
90°), and a rhombus (all sides are equal length).
AREA= 𝑎2
11. RECTANGLE
A rectangle is a four-sided shape where every
angle is a right angle (90°).
Also opposite sides are parallel and of equal
length.
𝐴𝑅𝐸𝐴 = 𝐿 × 𝐵
12. RHOMBUS
A rhombus is a four-sided shape where all sides have equal length.
Also opposite sides are parallel and opposite angles are equal.
Another interesting thing is that the diagonals (dashed lines in second
figure) meet in the middle at a right angle. In other words they "bisect"
(cut in half) each other at right angles.
A rhombus is sometimes called a rhomb or a diamond.
𝐴 =
𝑎×𝑏
2
; a is diagonal 1 and b is diagonal 2
13. KITE
Hey, it looks like a kite. It has two pairs of sides.
Each pair is made up of adjacent sides (they meet) that are equal in length.
The angles are equal where the pairs meet. Diagonals (dashed lines) meet at a right
angle, and one of the diagonal bisects (cuts equally in half) the other.
𝐴 =
𝑎×𝑏
2
; a is diagonal 1 and b is diagonal 2
14. PARALLELOGRAM
A parallelogram has opposite sides parallel and equal in length. Also
opposite angles are equal (angles "a" are the same, and angles "b" are
the same).
NOTE: Squares, Rectangles and Rhombuses are all Parallelograms!
𝐴 = 𝑏 × ℎ ; B is base , H is height
15. TRAPEZIUM
A trapezoid (called a trapezium in the UK) has a pair of
opposite sides parallel.
It is called an Isosceles trapezoid if the sides that aren't
parallel are equal in length and both angles coming from a
parallel side are equal, as shown.
And a trapezium (UK: trapezoid) is a quadrilateral with NO
parallel sides:
Trapezoid Trapezium
In the US: a pair of parallel sides NO parallel sides
In the UK: NO parallel sides a pair of parallel sides
(the US and UK definitions are swapped over!)
𝑨 =
𝒂+𝒃
𝟐
𝒉