PPT: Quadrilaterals | Mathematics Class 8- New NCERT (Ganita Prakash) PDF Download

 Page 1


Q u a d r i l a t e r a l s
Page 2


Q u a d r i l a t e r a l s
What is a Quadrilateral?
D e f i n i t i o n
A quadrilateral is a four-sided closed figure with four 
angles.
O r i g i n
The word comes from Latin:
quadri ³ four
latus ³ side
E x a m p l e s : square, rectangle, parallelogram, rhombus, kite, trapezium.
Page 3


Q u a d r i l a t e r a l s
What is a Quadrilateral?
D e f i n i t i o n
A quadrilateral is a four-sided closed figure with four 
angles.
O r i g i n
The word comes from Latin:
quadri ³ four
latus ³ side
E x a m p l e s : square, rectangle, parallelogram, rhombus, kite, trapezium.
R e c t a n g l e s
1
D e f i n i t i o n
A rectangle is a quadrilateral in which all angles are right angles (90°).
2
P r o p e r t i e s
All angles are 90°
Opposite sides are equal in length
Opposite sides are parallel
Page 4


Q u a d r i l a t e r a l s
What is a Quadrilateral?
D e f i n i t i o n
A quadrilateral is a four-sided closed figure with four 
angles.
O r i g i n
The word comes from Latin:
quadri ³ four
latus ³ side
E x a m p l e s : square, rectangle, parallelogram, rhombus, kite, trapezium.
R e c t a n g l e s
1
D e f i n i t i o n
A rectangle is a quadrilateral in which all angles are right angles (90°).
2
P r o p e r t i e s
All angles are 90°
Opposite sides are equal in length
Opposite sides are parallel
Diagonals of a Rectangle
Equal Length
The diagonals of a rectangle always have the same length.
Bisect Each Other
The diagonals of a rectangle always intersect at their midpoints.
Page 5


Q u a d r i l a t e r a l s
What is a Quadrilateral?
D e f i n i t i o n
A quadrilateral is a four-sided closed figure with four 
angles.
O r i g i n
The word comes from Latin:
quadri ³ four
latus ³ side
E x a m p l e s : square, rectangle, parallelogram, rhombus, kite, trapezium.
R e c t a n g l e s
1
D e f i n i t i o n
A rectangle is a quadrilateral in which all angles are right angles (90°).
2
P r o p e r t i e s
All angles are 90°
Opposite sides are equal in length
Opposite sides are parallel
Diagonals of a Rectangle
Equal Length
The diagonals of a rectangle always have the same length.
Bisect Each Other
The diagonals of a rectangle always intersect at their midpoints.
S q u a r e s
D e f i n i t i o n
A square is a quadrilateral in which:
All angles are 90°
All sides are of equal length
Every square is a rectangle, but not every 
rectangle is a square.