equilateral
obtuse-angled
acute-angled
scalene
congruent
vertex
right-angled
polygon
isosceles
line of symmetry
A triangle...
vertexes
side
angle
• is a closed figure
(polygon)
• has three sides
• has three vertexes
• has three interior
angles
Classifying Triangles
triangle
first name
middle name
last name
Which angle is the largest?
A
C
B
Which angle is the largest?
A
B
C
Which angle is the largest?
A
B
C
Possible Middle Names for
Triangles
obtuse-angled
right-angled
acute-angled
Classifying Triangles
acute-angled
or
obtuse-angled
or
triangle
right-angled
first name
middle name
last name
Equilateral Triangles
• 3 congruent sides
• 3 congruent angles
• 3 lines of symmetry
Isosceles Triangle
• 2 congruent sides
• 2 congruent angles
• 1 line of symmetry
Scalene Triangles
• 0 congruent sides
• 0 congruent angles
• 0 lines of symmetry
Classifying Triangles
equilateral
or
isosceles
or
acute-angled
or
obtuse-angled
or
scalene
right-angled
first name
middle name
triangle
last name
Give the first, middle and last
name for the following triangle:
isoscele
s
first name
Right-angled
middle name
triangle
last name
Give the first, middle and last
name for the following triangle:
isoscele
s
first name
obtuse-angled
middle name
triangle
last name
Give the first, middle and last
name for the following triangle:
equilateral
first name
acute-angled
middle name
triangle
last name
Give the first, middle and last
name for the following triangle:
scalene
first name
acute-angled
middle name
triangle
last name
Give the first, middle and last
name for the following triangle:
scalene
first name
Right-angled
middle name
triangle
last name
Recap: Classifying
Triangles
equilateral
or
isosceles
or
acute-angled
or
obtuse-angled
or
scalene
right-angled
first name
middle name
triangle
last name
Give the first, middle and last
name for the following triangle:
What is the
measure of
< A and < B
A
B
first name
middle name
last name
Name The Angle
What is the
measure of <
A and < B
A
B
first name
400
middle name
last name
Name The Angle:
What is the
measure of
< A and < B
A
300
first name
B
middle name
last name
Give the first, middle and last
name for the following triangle:
What is the
measure of
<A
A
300
first name
middle name
last name
Name The Angle
What is the
measure of
<A,<B,
and < C
A
B
first name
C
middle name
last name
What Can You Tell Me About
These Figures?
What Can You Tell Me About
This Figure?
What Can You Tell Me About
This Figure?
What Can You Tell Me About
This Figure?
What Can You Tell Me About
This Figure?
What Can You Tell Me About
This Figure?
Are These Figures
Congruent?