# Generalising angles in polygons (Part 2)

## Lesson details

### Key learning points

1. In this lesson, we will learn how to apply the generalisation of the total 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.
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
64800 degrees
720 degrees

## Exit quiz

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### 5 Questions

Q1.
If I split a 7 sided shape into 5 triangles, I have done the correct process to find the total interior angles within the shape.
False
Q2.
Which of the following WOULD give you the total interior angles within a n-sided polygon?
180n
360n
360n - 180
Q3.
Which of the following WOULD NOT give you the total interior angles of a n-sided polygon?
180(n - 2)
180n - 360
Q4.
The sum of the total interior angles in a 30 sided shape is...
504 degrees
540 degrees
5400 degrees
Q5.
What would be the correct calculation to work out the total sum of the interior angles in a decagon?