# Change the subject where the unknown appears twice

In this lesson, we will be changing the subject of a formula in which the unknown appears twice.

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!

Q1.1. What is the solution set for 10x² + 33x - 7≤ 0?

1/3

Q2.2. What is the solution set for 2x² + 2x – 30 < 5x + 24?

2/3

Q3.3. Which option is a quadratic inequality that has a solution set of {x: x >1.5 ∪ x < -0.5}?

3/3

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!

Q1.1. What is the solution set for 10x² + 33x - 7≤ 0?

1/3

Q2.2. What is the solution set for 2x² + 2x – 30 < 5x + 24?

2/3

Q3.3. Which option is a quadratic inequality that has a solution set of {x: x >1.5 ∪ x < -0.5}?

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.

Quiz:

# Change the subject where the unknown appears twice

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

Q1.Make t the subject of the formula.

1/3

Q2.Make b the subject of the formula.

2/3

Q3.Make x the subject of the formula.

3/3

Quiz:

# Change the subject where the unknown appears twice

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

Q1.Make t the subject of the formula.

1/3

Q2.Make b the subject of the formula.

2/3

Q3.Make x the subject of the formula.

3/3

# Lesson summary: Change the subject where the unknown appears twice

## 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