Similar triangles

In this lesson, we will learn to define similarity and apply your understanding to similar triangles. We will also draw an enlargement.

Unit quizzes are being retired in August 2023

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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.Which of these is an incomplete description of an enlargement?

1/5

Q2.Which of the following is the correct description of the below enlargement?

2/5

Q3.A shape has been enlarged and the image has a larger area and is in a different orientation to the object. Which of the following options could describe this enlargement?

3/5

Q4.A shape has been enlarged and the image has a smaller area than the object and is in the same orientation. Which of the following options could describe this enlargement?

4/5

Q5.A shape has been enlarged and the image has a smaller area than the object and has a different orientation. Which of the following options could describe this enlargement?

5/5

Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
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.Which of these is an incomplete description of an enlargement?

1/5

Q2.Which of the following is the correct description of the below enlargement?

2/5

Q3.A shape has been enlarged and the image has a larger area and is in a different orientation to the object. Which of the following options could describe this enlargement?

3/5

Q4.A shape has been enlarged and the image has a smaller area than the object and is in the same orientation. Which of the following options could describe this enlargement?

4/5

Q5.A shape has been enlarged and the image has a smaller area than the object and has a different orientation. Which of the following options could describe this enlargement?

5/5

Video

Click on the play button to start the video. If your teacher asks you to pause the video and look at the worksheet you should:

• Click "Close Video"
• Click "Next" to view the activity

Your video will re-appear on the next page, and will stay paused in the right place.

Worksheet

These slides will take you through some tasks for the lesson. If you need to re-play the video, click the ‘Resume Video’ icon. If you are asked to add answers to the slides, first download or print out the worksheet. Once you have finished all the tasks, click ‘Next’ below.

Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

Similar triangles quiz

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

Q1.Fill in the gap: if one shape is an enlargement of another, then these shapes are called ________ shapes.

1/5

Q2.Fill in the gap: in all similar shapes, corresponding __________ are equal.

2/5

Q3.Fill in the gap: corresponding sides of similar shapes are all enlarged by the same __________.

3/5

Q4.Are triangles ABC and LMN similar?

4/5

Q5.What is the scale factor of enlargement from ABC to LMN?

5/5

Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

Similar triangles quiz

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

Q1.Fill in the gap: if one shape is an enlargement of another, then these shapes are called ________ shapes.

1/5

Q2.Fill in the gap: in all similar shapes, corresponding __________ are equal.

2/5

Q3.Fill in the gap: corresponding sides of similar shapes are all enlarged by the same __________.

3/5

Q4.Are triangles ABC and LMN similar?

4/5

Q5.What is the scale factor of enlargement from ABC to LMN?

5/5

Lesson summary: Similar triangles

Time to move!

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For 5 mins...

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