Try to answer the following questions here:

• What is this question used for?
• What does this question assess?
• What does the student have to do?
• How is the question randomised?
• Are there any implementation details that editors should be aware of?

### History and Feedback

#### Checkpoint description

Describe what's changed since the last checkpoint.

#### heike hoffmann1 year, 3 months ago

Gave some feedback: Ready to use

#### heike hoffmann1 year, 3 months ago

Created this as a copy of Factorising: Common factor.
Distributive law: expanding one set of brackets Ready to use Ben Brawn 02/06/2016 06:48
Factorising: Common factor Ready to use Ben Brawn 02/06/2016 06:48
Distributive law: expanding one set of brackets draft steve kilgallon 23/08/2017 11:12
Expanding one set of brackets Needs to be tested Nasir Khan 05/08/2016 16:23
Distributive law: expanding one set of brackets draft Nasir Khan 29/07/2016 12:57
Algebra II:Expanding one set of brackets Ready to use Nasir Khan 12/08/2016 15:30
Algebra II:Expanding one set of brackets Ready to use Nasir Khan 12/08/2016 16:16
Expanding one set of brackets - with steps draft David Rickard 09/10/2016 16:15
Rachel's copy of Distributive law: expanding one set of brackets draft Rachel Staddon 20/04/2017 14:50
Distributive law: expanding one set of brackets draft Owen Jepps 11/01/2018 06:07
Marlon's copy of Factorising: Common factor draft Marlon Arcila 03/02/2018 16:30
Algebra II:Expanding one set of brackets draft heike hoffmann 14/11/2018 21:00
Factorising: Common factor Ready to use heike hoffmann 14/11/2018 21:07
Gemeenschappelijke factor afzonderen draft Johan Maertens 20/08/2019 15:38
Joshua's copy of Distributive law: expanding one set of brackets draft Joshua Calcutt 06/08/2019 05:55

Give any introductory information the student needs.

No variables have been defined in this question.

(a number)

Numbers between and (inclusive) with step size
A random number between and (inclusive) with step size

(text string)

(numbers)

(text strings)

This variable is an HTML node. HTML nodes can not be relied upon to work correctly when resuming a session - for example, attached event callbacks will be lost, and mathematical notation will likely also break.

If this causes problems, try to create HTML nodes where you use them in content areas, instead of storing them in variables.

Describe what this variable represents, and list any assumptions made about its value.

This variable doesn't seem to be used anywhere.

Name Type Generated Value

#### Error in variable testing condition

There's an error in the condition you specified in the Variable testing tab. Variable values can't be generated until it's fixed.

Error:

for seconds

Running for ...

No parts have been defined in this question.

Select a part to edit.

The correct answer is an equation. Use the accuracy tab to generate variable values satisfying this equation so it can be marked accurately.

#### Checking accuracy

Define the range of points over which the student's answer will be compared with the correct answer, and the method used to compare them.

#### Variable value generators

Give expressions which produce values for each of the variables in the expected answer. Leave blank to pick a random value from the range defined above, following the inferred type of the variable.

#### String restrictions

Both choices and answers must be defined for this part.

Help with this part type

##### Base marking algorithm

#### Test that the marking algorithm works

Check that the marking algorithm works with different sets of variables and student answers using the interface below.

Create unit tests to save expected results and to document how the algorithm should work.

There's an error which means the marking algorithm can't run:

Name Value

Note
Value Feedback

Click on a note's name to show or hide it. Only shown notes will be included when you create a unit test.

#### Unit tests

No unit tests have been defined. Enter an answer above, select one or more notes, and click the "Create a unit test" button.

The following tests check that the question is behaving as desired.

### This test has not been run yet This test produces the expected output This test does not produce the expected output

This test is not currently producing the expected result. Fix the marking algorithm to produce the expected results detailed below or, if this test is out of date, update the test to accept the current values.

One or more notes in this test are no longer defined. If these notes are no longer needed, you should delete this test.

Name Value

 This note produces the expected output

This test has not yet been run.

When you need to change the way this part works beyond the available options, you can write JavaScript code to be executed at the times described below.

Run this script the built-in script.

This script runs after the built-in script.

To account for errors made by the student in earlier calculations, replace question variables with answers to earlier parts.

In order to create a variable replacement, you must define at least one variable and one other part.

The variable replacements you've chosen will cause the following variables to be regenerated each time the student submits an answer to this part:

These variables have some random elements, which means they're not guaranteed to have the same value each time the student submits an answer. You should define new variables to store the random elements, so that they remain the same each time this part is marked.

### Parts

Give a worked solution to the whole question.

### Preamble

This script will run after the question's variable have been generated but before the HTML is attached.
Apply styling rules to the question's content.
This question is not used in any exams.