Finding missing angles in polygons

In this lesson, you will learn how to find an unknown angle in a polygon.

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.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.

1/5

Q2.Which of the following WOULD give you the total interior angles within a n-sided polygon?

2/5

Q3.Which of the following WOULD NOT give you the total interior angles of a n-sided polygon?

3/5

Q4.The sum of the total interior angles in a 30 sided shape is...

4/5

Q5.What would be the correct calculation to work out the total sum of the interior angles in a decagon?

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.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.

1/5

Q2.Which of the following WOULD give you the total interior angles within a n-sided polygon?

2/5

Q3.Which of the following WOULD NOT give you the total interior angles of a n-sided polygon?

3/5

Q4.The sum of the total interior angles in a 30 sided shape is...

4/5

Q5.What would be the correct calculation to work out the total sum of the interior angles in a decagon?

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 missing angles in polygons

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

Q1.A triangle is made up of the following: 73 degrees, 51 degrees and x degrees. Solve for x.

1/5

Q2.If a quadrilateral contains 3 right angles, what must the final angle be to form a quadrilateral?

2/5

Q3.If the angles in a decagon are the following: 73 degrees, 293 degrees, 203 degrees, 9 degrees, 29 degrees, 184 degrees, 173 degrees, 93 degrees, 208 degrees, y degrees. Solve for y.

3/5

Q4.Is it possible to have two obtuse angles in a triangle?

4/5

Q5.You are told that V + W + X + Y + Z = total interior sum of a pentagon. If V = 90 degrees, W = 110 degrees, X = 10 degrees, Y = 300 degrees, what would Z be?

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:

Finding missing angles in polygons

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

Q1.A triangle is made up of the following: 73 degrees, 51 degrees and x degrees. Solve for x.

1/5

Q2.If a quadrilateral contains 3 right angles, what must the final angle be to form a quadrilateral?

2/5

Q3.If the angles in a decagon are the following: 73 degrees, 293 degrees, 203 degrees, 9 degrees, 29 degrees, 184 degrees, 173 degrees, 93 degrees, 208 degrees, y degrees. Solve for y.

3/5

Q4.Is it possible to have two obtuse angles in a triangle?

4/5

Q5.You are told that V + W + X + Y + Z = total interior sum of a pentagon. If V = 90 degrees, W = 110 degrees, X = 10 degrees, Y = 300 degrees, what would Z be?

5/5

Lesson summary: Finding missing angles in polygons

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The next lesson in:
Angles in polygons
is:
Exterior angles

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