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This pdf includes the following topics:-

Types of Angles

Triangle Sum Theorem

Exterior Angle Theorem

Types of Angles

Triangle Sum Theorem

Exterior Angle Theorem

1.
Math Virtual Learning

8th Grade Math

Interior/Exterior Angles of a Triangle

April 10, 2020

8th Grade Math

Interior/Exterior Angles of a Triangle

April 10, 2020

2.
8th Grade Math

Lesson: April 10

Learning Target:

Student will identify interior and exterior angles of a

triangle.

Lesson Includes:

1) Angle Types

2)Triangle Sum Theorem

3) Exterior Angle Theorem

Lesson: April 10

Learning Target:

Student will identify interior and exterior angles of a

triangle.

Lesson Includes:

1) Angle Types

2)Triangle Sum Theorem

3) Exterior Angle Theorem

3.
Warm Up Activity

On a piece of paper, identify the following angles.

On a piece of paper, identify the following angles.

4.
Warm Up Activity Answers

Review the questions from the previous slide.

Acute Right Obtuse Acute

Review the questions from the previous slide.

Acute Right Obtuse Acute

5.
Instruction: Types of Angles

Read through the vocabulary and review the diagrams. Then watch the

video linked here.

1) Interior Angle: an angle inside a shape

2) Exterior Angle: is an angle outside of a shape, made

by the side of a shape and a line drawn out from an

adjacent side

3) Acute Angle: an angle that’s less than 90 degrees

4) Obtuse Angle: an angle that is greater than 90

5) Right Angle: a 90 degree angle

6) Complementary Angle: two angles that when added

together equal 90 degrees Today we are

7) Supplementary Angle: two angles that when added

mainly focusing on

Interior and

together equal 180 degree Exterior Angles!

Read through the vocabulary and review the diagrams. Then watch the

video linked here.

1) Interior Angle: an angle inside a shape

2) Exterior Angle: is an angle outside of a shape, made

by the side of a shape and a line drawn out from an

adjacent side

3) Acute Angle: an angle that’s less than 90 degrees

4) Obtuse Angle: an angle that is greater than 90

5) Right Angle: a 90 degree angle

6) Complementary Angle: two angles that when added

together equal 90 degrees Today we are

7) Supplementary Angle: two angles that when added

mainly focusing on

Interior and

together equal 180 degree Exterior Angles!

6.
Practice: Types of Angles

On a piece of paper: Identify the exterior and interior angles shown in the

problems.

1) 2)

3) 4)

On a piece of paper: Identify the exterior and interior angles shown in the

problems.

1) 2)

3) 4)

7.
Practice: Types of Angles ANSWERS

On a piece of paper: Identify the exterior and interior angles shown in the

1) 2)

3) 4)

On a piece of paper: Identify the exterior and interior angles shown in the

1) 2)

3) 4)

8.
Instruction: Triangle Sum Theorem

Read through the theorem and steps. Watch the provided video here. Then

review the examples on the next slide.

The triangle sum property states that the sum of the three

interior (inside the triangle) angles in a triangle is always

180 degrees.

1) Write an equation that adds all three angle

2) Set the equation equal to 180 degrees.

3) Solve for the variable.

4) Plug the value of the variable (the answer) back into any Don’t forget your steps

angle expression that you need to find the value of. for solving equations!

Read through the theorem and steps. Watch the provided video here. Then

review the examples on the next slide.

The triangle sum property states that the sum of the three

interior (inside the triangle) angles in a triangle is always

180 degrees.

1) Write an equation that adds all three angle

2) Set the equation equal to 180 degrees.

3) Solve for the variable.

4) Plug the value of the variable (the answer) back into any Don’t forget your steps

angle expression that you need to find the value of. for solving equations!

9.
Instruction: Triangle Sum Theorem

Review the examples. Directions: Solve for the variable, then find the missing

angle(s).

Review the examples. Directions: Solve for the variable, then find the missing

angle(s).

10.
Practice: Triangle Sum Theorem

On a piece of paper: Solve for the variable, then find the missing angle(s).

Question 1 Question 2

Question 3

On a piece of paper: Solve for the variable, then find the missing angle(s).

Question 1 Question 2

Question 3

11.
Practice: Triangle Sum Theorem Answers

Check your work from the previous slide. Additional practice linked on the last

slide.

Question 1

Question 3

Question 2

Check your work from the previous slide. Additional practice linked on the last

slide.

Question 1

Question 3

Question 2

12.
Instruction: Exterior Angle Theorem

Read through the theorem and steps. Watch the provided video here. Then

review the examples on the next slide.

The measure of an exterior angle of a triangle is

equal to the sum of the measures of the two

remote interior angles.

What if you are not given all the angles?

1) Write an equation: remote interior angle +

remote interior angle = exterior angle

2) Solve for the variable.

3) Plug the value of the variable (the answer) back

into any angle expression that you need to find the

value of.

Read through the theorem and steps. Watch the provided video here. Then

review the examples on the next slide.

The measure of an exterior angle of a triangle is

equal to the sum of the measures of the two

remote interior angles.

What if you are not given all the angles?

1) Write an equation: remote interior angle +

remote interior angle = exterior angle

2) Solve for the variable.

3) Plug the value of the variable (the answer) back

into any angle expression that you need to find the

value of.

13.
Instruction: Exterior Angle Theorem

Review the examples.

Review the examples.

14.
Practice: Exterior Angle Theorem

On a piece of paper: Solve for the variable, then find the missing angle(s).

3.

On a piece of paper: Solve for the variable, then find the missing angle(s).

3.

15.
Practice: Exterior Angles Theorem Answers

Check your work from the previous slide. Additional practice linked on the last

slide.

Question 1

Question 3

Question 2

Check your work from the previous slide. Additional practice linked on the last

slide.

Question 1

Question 3

Question 2

16.
Additional Practice:

Click on the links below to get additional practice and to check your

understanding!

Types of Angles

Triangle Sum Theorem

Exterior Angle Theorem

* May need to click twice for the links *

Click on the links below to get additional practice and to check your

understanding!

Types of Angles

Triangle Sum Theorem

Exterior Angle Theorem

* May need to click twice for the links *