# Subtract two surds

In this lesson, we will learn how to subtract one surd from another where no prior simplification is needed.In these cases, the surds will all have the same root.

#### 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 number is not a surd?

1/3

Q2.Simplify 6√7+5√7

2/3

Q3.A piece of wood has been cut up into three equal pieces as shown. What was the original total length of the piece of wood?

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.Which number is not a surd?

1/3

Q2.Simplify 6√7+5√7

2/3

Q3.A piece of wood has been cut up into three equal pieces as shown. What was the original total length of the piece of wood?

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:

# Subtract two surds

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

Q1.Simplify 6√2 - 4√2

1/3

Q2.Simplify 6√7 - 5√7

2/3

Q3.A piece of wood is shown. It is 7√5 m long. A piece of length 2√5 m is cut away. How long is the piece of wood now?

3/3

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

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

# Subtract two surds

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

Q1.Simplify 6√2 - 4√2

1/3

Q2.Simplify 6√7 - 5√7

2/3

Q3.A piece of wood is shown. It is 7√5 m long. A piece of length 2√5 m is cut away. How long is the piece of wood now?

3/3

# Lesson summary: Subtract two surds

## 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:
Chair yoga