# Generalising angles in polygons (Part 1)

## Lesson details

### Key learning points

1. In this lesson, we will learn how to generalise the sum of the interior angles in an n-sided polygon.

### Licence

This content is made available by Oak National Academy Limited and its partners and licensed under Oak’s terms & conditions (Collection 1), except where otherwise stated.

## Video

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## Worksheet

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## Starter quiz

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### 5 Questions

Q1.
The total sum of the interior angles of two triangles would be equal to...
180 degrees
540 degrees
90 degrees
Q2.
If I have a regular pentagon, how many triangles from one distinct point internally can I create?
1
4
5
Q3.
If I have a regular pentagon, what would the total interior angles sum to?
180 degrees
360 degrees
450 degrees
Q4.
If I have a regular octagon, how many triangles from one distinct point internally can I create?
4
5
8
Q5.
If I have a regular octagon, what would the total interior angles sum to?
1440 degrees
360 degrees
900 degrees

## Exit quiz

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### 5 Questions

Q1.
A megagon has how many sides?
10
100
10000
Q2.
How many internal triangles can be formed within a megagon?
10
1000
8
Q3.
How many internal triangles from a distinct point can be formed within an icosagon?
20
8
98
Q4.
The general formula for working out the total interior angles in a n-sided polygon is...
180(n-3)
360(n-2)
360n
Q5.
Using the formula, if I wanted to work out the total interior angles for a 360-sided shape, it would be...
360 degrees