Polygons and triangles

In this lesson, we will learn that the sum of the interior angles of a polygon can be found using triangles.

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!

Q1.ABCD forms a quadrilateral. What are the total interior angles of the quadrilateral?

1/5

Q2.Angle ABC is 98 degrees. What would the size of the reflex angle formed be on the exterior?

2/5

Q3.If I combined two equilateral triangles together with a shared side, what would the shape formed be called?

3/5

Q4.Which of the following is not a rule used so far for angles?

4/5

Q5.If A + B + C = 180, D + E = 180 and F is a right angle, what does A + B + C + D + E + F equal?

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!

Q1.ABCD forms a quadrilateral. What are the total interior angles of the quadrilateral?

1/5

Q2.Angle ABC is 98 degrees. What would the size of the reflex angle formed be on the exterior?

2/5

Q3.If I combined two equilateral triangles together with a shared side, what would the shape formed be called?

3/5

Q4.Which of the following is not a rule used so far for angles?

4/5

Q5.If A + B + C = 180, D + E = 180 and F is a right angle, what does A + B + C + D + E + F equal?

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:

Polygons and triangles

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

Q1.The total sum of the interior angles of two triangles would be equal to...

1/5

Q2.If I have a regular pentagon, how many triangles from one distinct point internally can I create?

2/5

Q3.If I have a regular pentagon, what would the total interior angles sum to?

3/5

Q4.If I have a regular octagon, how many triangles from one distinct point internally can I create?

4/5

Q5.If I have a regular octagon, what would the total interior angles sum to?

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:

Polygons and triangles

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

Q1.The total sum of the interior angles of two triangles would be equal to...

1/5

Q2.If I have a regular pentagon, how many triangles from one distinct point internally can I create?

2/5

Q3.If I have a regular pentagon, what would the total interior angles sum to?

3/5

Q4.If I have a regular octagon, how many triangles from one distinct point internally can I create?

4/5

Q5.If I have a regular octagon, what would the total interior angles sum to?

5/5

Lesson summary: Polygons and triangles

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Time to move!

Did you know that exercise helps your concentration and ability to learn?

For 5 mins...

Move around:
Climb stairs

On the spot:
Chair yoga