# Find areas of similar shapes given corresponding lengths

In this lesson, we will use the linear scale factor to calculate the area scale factor and find areas of similar shapes.

#### 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.Shape A maps to shape B in an enlargement, calculate the scale factor.

1/3

Q2.Why have corresponding vertices been joined up in shapes A and B with straight lines in this enlargement?

2/3

Q3.The point at (-2,-1) is enlarged by a scale factor of -2 from the centre of enlargement at (0,0). What will the new coordinate of the point be?

3/3

#### 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.Shape A maps to shape B in an enlargement, calculate the scale factor.

1/3

Q2.Why have corresponding vertices been joined up in shapes A and B with straight lines in this enlargement?

2/3

Q3.The point at (-2,-1) is enlarged by a scale factor of -2 from the centre of enlargement at (0,0). What will the new coordinate of the point be?

3/3

# 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:

# Find areas of similar shapes given corresponding lengths

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

Q1.Shape A and shape B are similar. Calculate the area of shape B.

1/4

Q2.Two similar triangles have heights of 2 cm and 10 cm. The area of the smaller triangle is 5 cm². Calculate the area of the larger triangle.

2/4

Q3.Complete the missing word:

3/4

Q4.Triangle A and triangle B are similar. Calculate the base length of triangle B.

4/4

#### Unit quizzes are being retired in August 2023

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

# Find areas of similar shapes given corresponding lengths

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

Q1.Shape A and shape B are similar. Calculate the area of shape B.

1/4

Q2.Two similar triangles have heights of 2 cm and 10 cm. The area of the smaller triangle is 5 cm². Calculate the area of the larger triangle.

2/4

Q3.Complete the missing word:

3/4

Q4.Triangle A and triangle B are similar. Calculate the base length of triangle B.

4/4

# Lesson summary: Find areas of similar shapes given corresponding lengths

## 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:
Dance