1) The document outlines a lesson plan taught by teacher Jaspreet Kaur to class 7 on the angle sum property of quadrilaterals. 2) The lesson uses lecture and demonstration methods, including a model to show how the four angles of a quadrilateral sum to 360 degrees. 3) Examples are worked through to prove the angle sum property and solve problems involving finding missing angles of quadrilaterals.

2. Pupil Teacher’s Name: Jaspreet Kaur
Pupil Teacher Roll No.: 100
Subject: Mathematics
Class: VII
Topic: Angle sum property of
Quadrilateral
Duration: 35 Minutes

3. General
Aids
A well Equipped Class Room with Chalk Board,
Duster, Pointer etc.
Specific
Aids
A model showing sum of four angles of
quadrilateral is 3600 (Angle sum property of
quadrilateral)
Instructiona
l Objectives
• To develop cognitive, conative and affective
abilities of students.
•To develop various skills, values and attitude in
students.
General
Aims
• To Develop the reasoning, thinking & imagination
powers of the students.
•To Enable them to make use of the mathematical
knowledge in day-to-day life.
•To provide opportunity for the development of
creative powers.

4. General
Objective
To make students to know about that sum of the four angles of
Quadrilateral is 3600.
Specific
objectives
After the completion of topic, the students will be able to
1. Prove angle sum property of Quadrilateral.
2. Solve problems based on angle sum property of Quadrilateral.
Previous
knowledge
assumed
1. Pupils are well acquainted with triangles.
2. They are well acquainted with angle sum property of triangle.
3. They are well acquainted with Quadrilateral.
Previous
knowledge
Testing
Pupil Teacher will ask the following questions -

5. Previous
Knowledge
Testing
Questions Answers
1. Name this figure (by
showing Triangle)
2. What is the Angle Sum
property of triangle?
3. Name this figure (by
showing another triangle)
4. Name this figure? (By
placing another triangle on
previous triangle that
makes it Quadrilateral).
5. What is the sum of the
angles of a Quadrilateral?
6. How will you prove this?
Triangle
Sum of three angles of triangles
is equal to 1800
Triangle
Quadrilateral
3600
No Response
Announcement
of Topic
On finding the most of the students unable to answer the last
question satisfactory. P.T. will announce the topic by saying, well
students today we’ll discuss how to prove angle sum properly of
Quadrilateral.

6. Presentation
P.T. will use Lecture – Cum –
Demonstration Method. Black Board
work was done side by side. Relevant
teaching aid will be used whenever
required.

7. Subject Matter P.T. Activity Pupil Response Chalk-Board Work
In Quadrilateral
ABCD, we have
two triangles, ∆
ABC & ∆ ACD
In ∆ ACB -
Mark A= 1 &
C = 3
In ∆ ACD ,
A= 2,
C=4
Name the first
triangle in this figure
which is blue in
Colour?
Name the second ∆
in this figure which is
pink in colour?
What is the sum of
Three angles of
∆ABC?
∆ ABC
∆ ACD
1+B+C=1800
∆ ABC Mark
A= 1 &
C = 3
In ∆ ACD ,
A= 2,
C=4
Sum of all angles
of triangles is
1800.
What is the sum of
three angles of
∆ADC?
2+D+4=
1800
In ∆ABC
1+B+C=1800
……..(1)

8. Subject
Matter
P.T. Activity Pupil Response Chalk-Board
Work
i.e. In ∆ADC
1+B+3 =
1800 ……..(1)
In ADC
2+D+4 =
1800 ……(2)
Add (1) & (2)
1+B+3
+2+D+4
= 1800 + 1800
(1 + 2) +
B +(3+4 )
+D = 3600
Therefore
A+B+C
+D = 3600
What is
1800+1800?
What is 1 +
2?
What is 3 +
4?
3600
A
C
Add (1) & (2)
1+B+3
+2+D+4 =
1800 + 1800
(1 + 2)+B+
(3+4)+D =
3600
Therefore
A+B+C
+D = 3600

9. Subject Matter P.T. Activity Pupil Response Chalk-Board Work
Question based
on Angle sum
property of
Quadrilateral.
Three angles of
quadrilateral are
1350, 600, 750
respectively Find
Fourth Angle
What is angle sum
property of
quadrilateral ABCD?
What is the value of
A?
What is the value of
B?
What is the value of
C?
A+B+C+D =
3600
1350
600
750
D C
X0 750
1350 600
A B
Let in Quadrilateral
ABCD
A=1350, B=600
C=750 & D=X0
Now A+B+C+D
= 3600
(Angle sum property
of Quadrilateral
1350+600+750+X0=36
00
2700+X0=3600
X0 = 3600-2700
X=900 , D=900

10. Subject Matter P.T. Activity Pupil Response Chalk-Board Work
Sectional Recapitulation
• What is angle sum property of
Quadrilateral?
• In a Quadrilateral ABCD, D=1200,
A=400, B=400 Find forth angle i.e. C
The Four angles
of a
Quadrilateral
are in the ratio
of 1:2:3:4. find
all the four
angles.
What is angle sum
property of
Quadrilateral
ABCD?
What is the value
of A?
What is the value
of B?
What is the value
of C?
A+B+C+D =
3600
X0
Y0
3X0
Let A= X0
B = 2X0
C = 3X0
D = 4X0
A+B+C+D =
3600
X0+2X0+3X0+4X0=
3600
10X0 = 3600
X0 = 3600/100
X0=360
A = X0= 360
B = 2X0
= 2(36)0
= 720

11. Subject Matter P.T. Activity Pupil Response Chalk-Board
Work
What is the value
of D?
What is the Value
of X0?
4X0
360
C =3X0
=3(360)
=1080
D = 4X0
=4(360)
=1440
A=360
B=720, C=1080
D=1440

12. Final Recapitalization:
If three angles of a Quadrilateral are in the ratio of
1:2:3. If the sum of smallest and largest angle from
these angles is 1800 then find all the angles of
quadrilateral.
Home Work:
The four angles of a quadrilateral are in the ratio
2:3:4:5. Find all the angles.

13. Audio Visual Aid Used:
D C
4
3 D 4 C
3
2
1
2
1
A B A B