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GGEEOOMMEETTRRYY 
PPRREESSEENNTTAATTIIOONN 
PRESENTED BY: 
SHAGUFTA KHAN
SHAPES 
LINES 
ANGLES 
Special 4 
sides 
Types of 
Triangle 
Area and 
Measurement 
isosceles 
triangle 
equilateral 
Right 
square 
circle Rhombu 
rectangular trapezium 
s 
h 
Base base 
area=1/2*base*height 
rectangular 
Square 
Rho 
mbu 
s 
parallelogram
What did the 
acorn say when 
he grew up? 
Circles Polygons 
Points 
Lines 
Planes 
Congruency 
Similarity
Content 
Introduction. 
Objectives/Importance. 
Curriculum Alignment. 
Basic Geometrical Concepts. 
Construction of Triangle. 
Area of Triangle. 
Activities to teach. 
Misconception and Issue.
CURRICULUM ALLIGNMENT 
Shapes, its kinds and classification 
Lines, Angles and its types. 
Measurements( Area and 
Parameter) 
Use of Protractor and Scale to 
measure.
What is Geometry 
& 
their IMPORTANCE 
Geometry is the study of 
shapes 
They studied Geometry in 
Ancient Mesopotamia & Ancient 
Egypt 
Geometry is important 
in the art and construction 
fields
INTRODUCTION 
Plane Geometry is about flat shapes 
like lines, circles and triangles ... shapes 
that can be drawn on a piece of paper 
Solid Geometry is about three 
dimensional objects like cubes, 
prisms, cylinders and spheres.
Point, Line, Plane and Solid 
A Point has no dimensions, 
only position 
A Line is one-dimensional 
A Plane is two dimensional 
(2D) 
A Solid is three-dimensional 
(3D) 
Ray: A line with a start 
point but no end point
LINES 
• STRAIGHT LINE: A line with 
constant direction. 
• CURVED LINE: A line that is bent 
without an angle.
OPEN & CLOSED 
FIGURES 
• A CLOSED FIGURE/SHAPE starts 
and ends at the same point. 
• An OPEN FIGURE/SHAPE does NOT 
start and end at the same point. 
CLOSED OPEN 
● 
● 
● 
Start 
End 
Star 
t 
End
ACTIVITY 1
Line segment LINE 
If a line is cute at two 
parts, then the part of a 
line between the cuts is 
called ‘LINE SEGMENT’. It 
has two end points. 
SEGMENT 
A B 
Line segment
PARALLEL AND PERPENDICULAR 
LINES 
• PARALLEL LINES: 
Two equal distance lines 
that never meet each Other 
even if they stretched unlimited. 
PERPENDICULAR LINES: 
Lines that are at right 
angles (90°) to each 
other
MEASURING LENGTH 
• You can measure how long things are, 
or how tall, or how far apart they are. 
Those are all examples of length 
measurements. 
Example: This fork is 20 centimeters 
long
ANGLE 
• The two straight 
lines that have a 
common end is 
called angle.
HOW MANY ANGLES 
DOES EACH HAVE?
COMPLEMENTARY ANGLE 
• Two angles are complementary if the sum of 
their angles equals 90o. 
If one angle is known, its complementary 
angle can be found by subtracting the 
measure of its angle from 90o. 
• Example: What is the complementary angle 
of 43o? 
Solution: 90o - 43o = 47o
SUPPLIMENTARY ANGLE 
• Two angles are supplementary if the 
sum of their angles equals 180o. 
If one angle is known, its 
supplementary angle can be found by 
subtracting the measure of its angle 
from 180o. 
• Example: What is the supplementary 
angle of 143o? 
Solution: 180o - 143o = 37o
DIFFERENT TYPES OF ANGLE 
• Acute Angle an angle that is less than 90° 
• Right Angle an angle that is 90° exactly 
• Obtuse Angle an angle that is greater than 
90° but 
less than 180° 
• Straight Angle an angle that is 180° exactly 
• Reflex Angle an angle that is greater than 
180°
AREA 
• Surface of any shape/figure, covered 
by lines is called area. 
FFIINNDDIINNDD AARREEAA (( LLxxBB)) 
Question: LOOK AT THE FOLLOWING 
FIGURE AND GIVE THE AREA IN 
SQUARE Cm2
PERIMETER 
The distance around a two dimensional shape. 
The perimeter of this 
regular pentagon is 
3+3+3+3+3 = 5×3 = 
15 
The perimeter of this 
rectangle is 7+3+7+3 
= 20 
rrgghghghhhhhhhh 
hhhhhhhhhhhhhhh 
hhhhhhhhhhhhhhh 
hhhhhhhhhhhhhhh 
hhhhhhhhhhhhhhh 
hhh
MEASUREMENT OF PERIMETER 
• Rectangle 
Area = w × h 
w = width 
h = height 
• Square 
Area = a2 
a = length of 
side
SHAPES WITH SAME AREA CAN 
HAVE DIFFERENT PERIMETER 
2cm 
2cm 
1cm 
1cm 
AREA=4cm 
2 
Perimeter=8cm 
Area=6cm 2 
Perimeter= 10cm
HERE IS THE SITE PLANE OF A 
HOUSE. FIND AREA AND 
PERIMETER?
Circle 
• In a plane, each point of the circle is at equal 
distance from a fixed point. The fixed point is 
called the centre of the circle. 
• The distance from centre to any point on the 
circle is called radius of the circle. 
• A Line segment passing through the centre of 
the circle and whose end points lie on the 
circle is called the diameter of the circle. 
• The length of the circle or the distance 
around it is called circumference of the 
circle. 
circle 
0 
Radius 
Diameter 
D=2r 
circumference
Using a Protractor 
• Helps you measure angles (in degrees) 
• Protractors usually have two sets of 
numbers going 
in opposite directions 
• Each row of half 
• Protractor=180°
KINDS OF TRIANGLE
Constructing a triangle given SAS 
How could we construct a triangle given the lengths 
of two of its sides and the angle between them? 
side 
side 
angle 
The angle between the two sides is often called 
the included angle. 
We use the abbreviation SAS to stand 
for Side, Angle and Side.
Constructing a triangle given ASA 
How could we construct a triangle given 
two angles and the length of the side 
between them? 
side 
angle 
angle 
The side between the two angles is often called 
the included side. 
We use the abbreviation ASA to stand for 
Angle, Side and Angle.
Constructing a triangle given SSS 
How could we construct a triangle 
given the lengths of three sides? 
side side 
side 
Hint: We would need to use a compass. 
We use the abbreviation SSS to stand 
for Side, Side, Side.
Constructing a triangle given RHS 
Remember, the longest side in a right-angled 
triangle is called the hypotenuse. 
How could we construct a right-angled triangle 
given the right angle, the length of the 
hypotenuse and the length of one other side? 
hypotenuse 
right angle 
side 
We use the abbreviation RHS to stand 
for Right angle, Hypotenuse and Side.
Examples 
• 1 What is the area of this square? 
• Solution 
• Area = s × s 
• = 3.2 × 3.2 
• = 1024 cm2 
• 2 What is the area of this rectangle? 
• Solution 
• Area = l × b 6 cm = 60 mm 
• = 60 × 5 
• = 300 mm2
Areas of composite shapes 
• Find the area of this shape. 
• Solution 
• Method 1 
• Area of shape = area of rectangle Y + 
area of square X 
• = (6 × 2) + (3 × 3) 
• = 12 + 9 
• = 21 cm2
What about this shaded area? 
• Area of purple shape = area of big 
rectangle − area of small 
rectangle 
• = (75 × 45) − (32 × 24) 
• = 3375 − 768 
• = 2607 mm2
• What shapes can you see? 
• Solution 
• Divide the shape into a 
triangle and a rectangle. 
• Area of shape = area of rectangle + area of 
triangle 
• = (16 × 14) + (½ × 14 × 14) 
• = 224 + 98 
224cm2 
• = 322 cm2 
A = 
½bh 
98cm2
MISCONCEPTIONS IN GEOMETRY 
•Identifying the Base and Height of a 
Triangle. 
•Conservation Misconception 
•Angles: Larger Space means Larger Angle 
•Shape Properties 
•Orientation and Rotation of Shapes 
•Perpendicular lines 
•There Are Four Sorts Of Triangle: Scalene, 
Isosceles, Equilateral And Right-Angled
Once you study all the “fancy words”, 
Geometry is very easy to understand… 
so STUDY! 
Thank you

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Basic concept of geometry

  • 2.
  • 3. SHAPES LINES ANGLES Special 4 sides Types of Triangle Area and Measurement isosceles triangle equilateral Right square circle Rhombu rectangular trapezium s h Base base area=1/2*base*height rectangular Square Rho mbu s parallelogram
  • 4. What did the acorn say when he grew up? Circles Polygons Points Lines Planes Congruency Similarity
  • 5. Content Introduction. Objectives/Importance. Curriculum Alignment. Basic Geometrical Concepts. Construction of Triangle. Area of Triangle. Activities to teach. Misconception and Issue.
  • 6. CURRICULUM ALLIGNMENT Shapes, its kinds and classification Lines, Angles and its types. Measurements( Area and Parameter) Use of Protractor and Scale to measure.
  • 7. What is Geometry & their IMPORTANCE Geometry is the study of shapes They studied Geometry in Ancient Mesopotamia & Ancient Egypt Geometry is important in the art and construction fields
  • 8.
  • 9. INTRODUCTION Plane Geometry is about flat shapes like lines, circles and triangles ... shapes that can be drawn on a piece of paper Solid Geometry is about three dimensional objects like cubes, prisms, cylinders and spheres.
  • 10. Point, Line, Plane and Solid A Point has no dimensions, only position A Line is one-dimensional A Plane is two dimensional (2D) A Solid is three-dimensional (3D) Ray: A line with a start point but no end point
  • 11. LINES • STRAIGHT LINE: A line with constant direction. • CURVED LINE: A line that is bent without an angle.
  • 12. OPEN & CLOSED FIGURES • A CLOSED FIGURE/SHAPE starts and ends at the same point. • An OPEN FIGURE/SHAPE does NOT start and end at the same point. CLOSED OPEN ● ● ● Start End Star t End
  • 14. Line segment LINE If a line is cute at two parts, then the part of a line between the cuts is called ‘LINE SEGMENT’. It has two end points. SEGMENT A B Line segment
  • 15. PARALLEL AND PERPENDICULAR LINES • PARALLEL LINES: Two equal distance lines that never meet each Other even if they stretched unlimited. PERPENDICULAR LINES: Lines that are at right angles (90°) to each other
  • 16. MEASURING LENGTH • You can measure how long things are, or how tall, or how far apart they are. Those are all examples of length measurements. Example: This fork is 20 centimeters long
  • 17. ANGLE • The two straight lines that have a common end is called angle.
  • 18. HOW MANY ANGLES DOES EACH HAVE?
  • 19. COMPLEMENTARY ANGLE • Two angles are complementary if the sum of their angles equals 90o. If one angle is known, its complementary angle can be found by subtracting the measure of its angle from 90o. • Example: What is the complementary angle of 43o? Solution: 90o - 43o = 47o
  • 20. SUPPLIMENTARY ANGLE • Two angles are supplementary if the sum of their angles equals 180o. If one angle is known, its supplementary angle can be found by subtracting the measure of its angle from 180o. • Example: What is the supplementary angle of 143o? Solution: 180o - 143o = 37o
  • 21. DIFFERENT TYPES OF ANGLE • Acute Angle an angle that is less than 90° • Right Angle an angle that is 90° exactly • Obtuse Angle an angle that is greater than 90° but less than 180° • Straight Angle an angle that is 180° exactly • Reflex Angle an angle that is greater than 180°
  • 22. AREA • Surface of any shape/figure, covered by lines is called area. FFIINNDDIINNDD AARREEAA (( LLxxBB)) Question: LOOK AT THE FOLLOWING FIGURE AND GIVE THE AREA IN SQUARE Cm2
  • 23. PERIMETER The distance around a two dimensional shape. The perimeter of this regular pentagon is 3+3+3+3+3 = 5×3 = 15 The perimeter of this rectangle is 7+3+7+3 = 20 rrgghghghhhhhhhh hhhhhhhhhhhhhhh hhhhhhhhhhhhhhh hhhhhhhhhhhhhhh hhhhhhhhhhhhhhh hhh
  • 24. MEASUREMENT OF PERIMETER • Rectangle Area = w × h w = width h = height • Square Area = a2 a = length of side
  • 25. SHAPES WITH SAME AREA CAN HAVE DIFFERENT PERIMETER 2cm 2cm 1cm 1cm AREA=4cm 2 Perimeter=8cm Area=6cm 2 Perimeter= 10cm
  • 26. HERE IS THE SITE PLANE OF A HOUSE. FIND AREA AND PERIMETER?
  • 27. Circle • In a plane, each point of the circle is at equal distance from a fixed point. The fixed point is called the centre of the circle. • The distance from centre to any point on the circle is called radius of the circle. • A Line segment passing through the centre of the circle and whose end points lie on the circle is called the diameter of the circle. • The length of the circle or the distance around it is called circumference of the circle. circle 0 Radius Diameter D=2r circumference
  • 28. Using a Protractor • Helps you measure angles (in degrees) • Protractors usually have two sets of numbers going in opposite directions • Each row of half • Protractor=180°
  • 30. Constructing a triangle given SAS How could we construct a triangle given the lengths of two of its sides and the angle between them? side side angle The angle between the two sides is often called the included angle. We use the abbreviation SAS to stand for Side, Angle and Side.
  • 31. Constructing a triangle given ASA How could we construct a triangle given two angles and the length of the side between them? side angle angle The side between the two angles is often called the included side. We use the abbreviation ASA to stand for Angle, Side and Angle.
  • 32. Constructing a triangle given SSS How could we construct a triangle given the lengths of three sides? side side side Hint: We would need to use a compass. We use the abbreviation SSS to stand for Side, Side, Side.
  • 33. Constructing a triangle given RHS Remember, the longest side in a right-angled triangle is called the hypotenuse. How could we construct a right-angled triangle given the right angle, the length of the hypotenuse and the length of one other side? hypotenuse right angle side We use the abbreviation RHS to stand for Right angle, Hypotenuse and Side.
  • 34. Examples • 1 What is the area of this square? • Solution • Area = s × s • = 3.2 × 3.2 • = 1024 cm2 • 2 What is the area of this rectangle? • Solution • Area = l × b 6 cm = 60 mm • = 60 × 5 • = 300 mm2
  • 35. Areas of composite shapes • Find the area of this shape. • Solution • Method 1 • Area of shape = area of rectangle Y + area of square X • = (6 × 2) + (3 × 3) • = 12 + 9 • = 21 cm2
  • 36. What about this shaded area? • Area of purple shape = area of big rectangle − area of small rectangle • = (75 × 45) − (32 × 24) • = 3375 − 768 • = 2607 mm2
  • 37. • What shapes can you see? • Solution • Divide the shape into a triangle and a rectangle. • Area of shape = area of rectangle + area of triangle • = (16 × 14) + (½ × 14 × 14) • = 224 + 98 224cm2 • = 322 cm2 A = ½bh 98cm2
  • 38. MISCONCEPTIONS IN GEOMETRY •Identifying the Base and Height of a Triangle. •Conservation Misconception •Angles: Larger Space means Larger Angle •Shape Properties •Orientation and Rotation of Shapes •Perpendicular lines •There Are Four Sorts Of Triangle: Scalene, Isosceles, Equilateral And Right-Angled
  • 39. Once you study all the “fancy words”, Geometry is very easy to understand… so STUDY! Thank you