Slide 1 : T R I A N G L E S A triangle is a geometrical figure
It is formed by three line segments
The line segments is termed as sides of the triangle
There is a common end point when the sides taken in pairs
The common end point is termed as vertex of the triangle A triangle is a closed plane figure
bounded by three line segments.
Slide 2 : T R I A N G L E S Y Z X A triangle has six components:
3 sides and 3 angles
In ∆XYZ,
Sides : XY, YZ, XZ
Vertices: X, Y, Z
Three angles are formed at three vertices
Angles : X, Y, Z
Slide 3 : TYPES OF TRIANGLE Based on sides Based on angles
Slide 4 : Based on sides T R I A N G L E S Scalene Triangle Isosceles Triangle Equilateral Triangle
Slide 5 : Based on angles T R I A N G L E S Acute angled Triangle Right angled Triangle Obtuse angled Triangle
Slide 6 : SCALENE TRIANGLE The sides are unequal B a s e d o n s i d e s
Slide 7 : ISOSCELES TRIANGLE The two lateral sides are equal B a s e d o n s i d e s
Slide 8 : EQUILATERAL TRIANGLE The three sides are equal B a s e d o n s i d e s
Slide 9 : Acute angled triangle Triangle with all the three angles less than 900 B a s e d o n a n g l e s
Slide 10 : Right angled triangle Triangle with any one angle equal to 900 B a s e d o n a n g l e s
Slide 11 : Obtuse angled triangle Triangle with any one angle greater than 900 B a s e d o n a n g l e s
Slide 12 : I. Classify each of the following triangles
according to the lengths of their sides: II. Classify each of the following triangles
according to the size of their angles
: TRIANGLES ? ?
Slide 13 : TRIANGLES Identify the following triangles: Angle A = 90 Angle B = 1, Angle C = 89 degrees Angle A = 112 Angle B = 7, Angle C = 61 degrees Angle A = 54 Angle B = 30, Angle C = 96 degrees Angle A = 56 Angle B = 72, Angle C = 52 degrees Side A = 12 cm., Side B = 12 cm., Side C = 12 cm. Side A = 15 cm., Side B = 7 cm., Side C = 13 cm. Side A = 22 cm., Side B = 22 cm., Side C = 23 cm.