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equilateral

obtuse-angled

acute-angled

scalene

Triangles

congruent

vertex

polygon

right-angled

isosceles

line of symmetry

A triangle...

vertexes

- is a closed figure (polygon)
- has three sides
- has three vertexes
- has three interior angles

side

angle

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

C

B

Possible Middle Names for Triangles

obtuse-angled

right-angled

acute-angled

Classifying Triangles

acute-angled or obtuse-angled or right-angled

triangle

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 scalene

acute-angled or obtuse-angled or right-angled

triangle

first name middle name last name

Give the first, middle and last name for the

following triangle

isosceles

Right-angled

triangle

first name middle name last name

Give the first, middle and last name for the

following triangle

triangle

obtuse-angled

isosceles

first name middle name last name

Give the first, middle and last name for the

following triangle

triangle

acute-angled

equilateral

first name middle name last name

Give the first, middle and last name for the

following triangle

triangle

acute-angled

scalene

first name middle name last name

Give the first, middle and last name for the

following triangle

triangle

Right-angled

scalene

first name middle name last name

End of Part 1

Recap Classifying Triangles

equilateral or isosceles or scalene

acute-angled or obtuse-angled or right-angled

triangle

first name middle name last name

Give the first, middle and last name for the

following triangle

What is the measure of lt A and lt B

A

B

first name middle name last name

Name The Angle

What is the measure of lt A and lt B

A

B

400

first name middle name last name

Name The Angle

What is the measure of lt A and lt B

A

300

B

first name middle name last name

Give the first, middle and last name for the

following triangle

What is the measure of lt A

A

300

first name middle name last name

Name The Angle

What is the measure of lt A , lt B , and lt C

A

B

C

first name 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?