The document defines and describes different types of triangles. It begins by defining a triangle as a polygon with three edges and vertices. Triangles are then classified based on their sides and angles. There are three types of triangles based on sides: equilateral triangles have three equal sides and three equal angles; isosceles triangles have two equal sides and two equal base angles; and scalene triangles have no equal sides and three unequal angles. Key properties of each triangle type are provided.

1. Made By:- B .AROKIYA.RAJ
21-EDM-23
Subject :- Maths
Class:-8th

2. topic
TRIANGLES & its TYPES

3. What is triangle?
A triangle is a polygon
with three edges and
three vertices. It is one of
the basic shapes in
geometry. A triangle with
vertices say A, B, and C is
denoted ΔABC.

4. Types of triangle
• Triangles are classified on the basis of:
– Sides
– Angles

5. Types of triangle on the basis of
sides
• Equilateral triangle
• Isosceles triangle
• Scalene triangle

6. Equilateral triangle
• It has 3 equal sides.
• It has 3 equal angles.
• Since the sum of the interior angles is 180
degrees, every angle of an equilateral
triangle is 60 degrees.
• It is a regular polygon with 3 sides.
• The altitude and median from a vertex is
the same single line.
• The ortho-centre and centroid of the
triangle is the same point.

7. Isosceles triangle
• It has two equal sides.
• It has two equal angles, that is, the base
angles.
• When the third angle is 90 degrees, it is
called a right isosceles triangle.
• The altitude from the apex to the base
bisects the angle at the apex.

8. Scalene triangle
• It has no equal sides, i.e. all the sides are
unequal.
• All the three angle are unequal, but the
sum of all the angle is 180 degree

9. Closure
So, studied today we studied about:
• Triangle
• Classification of triangle on basis of:
– Sides
– Angles
• Types of triangle on basis of sides:
• Equilateral triangle
• Isosceles triangle
• Scalene triangle

10. Home Assignment