PPT: Quadrilaterals | Mathematics (Maths) Class 9 PDF Download

 Page 1


Quadrilaterals
Mathematics Class 9
Page 2


Quadrilaterals
Mathematics Class 9
Quadrilateral
A quadrilateral is a two-dimensional shape with four
sides.
The term "quadrilateral" comes from Latin, where
"quad" means "four" and "lateral" means "side."
Page 3


Quadrilaterals
Mathematics Class 9
Quadrilateral
A quadrilateral is a two-dimensional shape with four
sides.
The term "quadrilateral" comes from Latin, where
"quad" means "four" and "lateral" means "side."
St ate m e n t: The sum of the four angles of a
quadrilateral is 360°.
ANGLE SUM PROPERTY OF A QUADRILATERAL
And we know the angle sum property of a
triangle i.e. the sum of all the three angles of
a triangle is 180°.
If we draw a diagonal in the quadrilateral
(i. AC) , it divides it into two triangles.
Proof
Page 4


Quadrilaterals
Mathematics Class 9
Quadrilateral
A quadrilateral is a two-dimensional shape with four
sides.
The term "quadrilateral" comes from Latin, where
"quad" means "four" and "lateral" means "side."
St ate m e n t: The sum of the four angles of a
quadrilateral is 360°.
ANGLE SUM PROPERTY OF A QUADRILATERAL
And we know the angle sum property of a
triangle i.e. the sum of all the three angles of
a triangle is 180°.
If we draw a diagonal in the quadrilateral
(i. AC) , it divides it into two triangles.
Proof
ANGLE SUM PROPERTY OF A QUADRILATERAL
The sum of angles of ?ADC = 180°.
The sum of angles of ?ABC = 180°.
By adding both we get ?A + ?B +
?C + ?D = 360°
Hence, the sum of the four angles
of a quadrilateral is 360°.
Page 5


Quadrilaterals
Mathematics Class 9
Quadrilateral
A quadrilateral is a two-dimensional shape with four
sides.
The term "quadrilateral" comes from Latin, where
"quad" means "four" and "lateral" means "side."
St ate m e n t: The sum of the four angles of a
quadrilateral is 360°.
ANGLE SUM PROPERTY OF A QUADRILATERAL
And we know the angle sum property of a
triangle i.e. the sum of all the three angles of
a triangle is 180°.
If we draw a diagonal in the quadrilateral
(i. AC) , it divides it into two triangles.
Proof
ANGLE SUM PROPERTY OF A QUADRILATERAL
The sum of angles of ?ADC = 180°.
The sum of angles of ?ABC = 180°.
By adding both we get ?A + ?B +
?C + ?D = 360°
Hence, the sum of the four angles
of a quadrilateral is 360°.
Quadrilaterals
Types of