Hello! Triangles are the main topic about this presentation. Hope you enjoy it!

2. Characteristics
and Definition
Classification
by Side
In geometry…
A triangle is a closed, two-dimensional
shape. It is also a polygon.
It consists of 3 sides and 3 angles.
Classification
by Angle
Interior
Angles
Exterior
Angles
Perimeter of
a Triangle
Area of
a Triangle
Characteristics and Definition

3. Characteristics
and Definition
Classification
by Side
Scalene:
- all the three sides have different measures
Isosceles:
- two sides have equal length
Equilateral:
- all three sides are equal
Classification
by Angle
Interior
Angles
Exterior
Angles
Perimeter of
a Triangle
Area of
a Triangle
Classification by Side

4. Characteristics
and Definition
Classification
by Side
Acute:
- all of its angles are less than 90°
Right:
- one of the angles is equal to 90°
Obtuse:
- only one of its angles is more than 90°
Classification
by Angle
Interior
Angles
Exterior
Angles
Perimeter of
a Triangle
Area of
a Triangle
Classification by Angle

5. Characteristics
and Definition
Classification
by Side
All of the three interior angles of a triangle always
sum up to 180°.
Since all the interior angles of the triangle add up
to 180 degrees, every angle must be less than 180°.
Classification
by Angle
Interior
Angles
Exterior
Angles
Perimeter of
a Triangle
Area of
a Triangle
Interior Angles

6. Characteristics
and Definition
Classification
by Side
All of the three exterior angles of a triangle always
sum up to 360°.
Every exterior angle is supplementary to its
interior angle, therefore, every pair of an interior
and exterior angle must sum up to 180°.
Classification
by Angle
Interior
Angles
Exterior
Angles
Perimeter of
a Triangle
Area of
a Triangle
Exterior Angles

7. Characteristics
and Definition
Classification
by Side
The perimeter of a triangle can be defined as the
sum of all the sides of a triangle.
A triangle has three sides.
Perimeter of a Triangle = Sum of all 3 sides.
Classification
by Angle
Interior
Angles
Exterior
Angles
Perimeter of
a Triangle
Area of
a Triangle
Perimeter of a Triangle

8. Characteristics
and Definition
Classification
by Side
The area of a triangle can be defined as the half of
the product of its base and height.
Base = b
Height = h
Area of a Triangle =
𝒃𝒉
𝟐
Classification
by Angle
Interior
Angles
Exterior
Angles
Perimeter of
a Triangle
Area of
a Triangle
Area of a Triangle