Finding the sum of interior angles in a polygon

Calculate the sum of interior angles in polygons, and apply this to find missing angles.

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Question 1

Question 2

Question 3

Question 4

Question 5

Q1.What is the sum of exterior angles of any polygon?

1/5

Q2.Calculate the size of angle a.

2/5

Q3.Calculate the size of angle b.

3/5

Q4.4. What is the size of each exterior angle of a regular 15 sided polygon?

4/5

Q5.5. A regular polygon has an exterior angle of 30º. How many sides does it have?

5/5

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Question 1

Question 2

Question 3

Question 4

Question 5

Q1.What is the sum of exterior angles of any polygon?

1/5

Q2.Calculate the size of angle a.

2/5

Q3.Calculate the size of angle b.

3/5

Q4.4. What is the size of each exterior angle of a regular 15 sided polygon?

4/5

Q5.5. A regular polygon has an exterior angle of 30º. How many sides does it have?

5/5

Video

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Worksheet

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This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Finding the Sum of Interior Angles

Don’t worry if you get a question wrong! Forgetting is an important step in learning. We will recap next lesson.

Question 1

Question 2

Question 3

Question 4

Q1.What is the sum of interior angles of a 20-sided shape?

1/4

Q2.What is the sum of interior angles of a 9-sided shape?

2/4

Q3.What is the missing angle, labelled x?

3/4

Q4.What is the size of each interior angle in a regular octagon?

4/4

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Finding the Sum of Interior Angles

Don’t worry if you get a question wrong! Forgetting is an important step in learning. We will recap next lesson.

Question 1

Question 2

Question 3

Question 4

Q1.What is the sum of interior angles of a 20-sided shape?

1/4

Q2.What is the sum of interior angles of a 9-sided shape?

2/4

Q3.What is the missing angle, labelled x?

3/4

Q4.What is the size of each interior angle in a regular octagon?

4/4

Lesson summary: Finding the sum of interior angles in a polygon

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