Source: https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-a-compendium-of-mathematical-methods-seneca-certified/3-1-6-method-f-vertical-and-crosswise

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# Method F - Vertical & Crosswise

CPD: A Compendium of Mathematical Methods (By Jo Morgan), topic 3.1.6

## Vertical and Cross: Expand and Simplify (x + 3)(x − 5)

### Step 1

![Step 1](https://image-v2.cdn.app.senecalearning.com/2020-04/72f96ba0-f156-49a5-9336-503c585429a4/Method%20F%20-%20Example%201.png)

- Write (x + 3)(x − 5) in two rows, in a similar way to a column multiplication.

### Step 2

![Step 2](https://image-v2.cdn.app.senecalearning.com/2020-04/e28ee21a-0357-4fa2-a1d1-c3383710c5f5/Method%20F%20-%20Example%201%20(1).png)

- First, multiply vertically. 
- The first two terms in each expression are multiplied together and the product is written at the bottom.

### Step 3

![Step 3](https://image-v2.cdn.app.senecalearning.com/2020-04/50387aa2-a69a-4690-9199-4ae56c63e4d3/Method%20F%20-%20Example%201%20(2).png)

- Now, multiply vertically again – this time the last two terms in each expression are multiplied together and the product is written at the bottom.

### Step 4

![Step 4](https://image-v2.cdn.app.senecalearning.com/2020-04/dc3720fa-3c41-4044-8d42-8403b847b3cb/Method%20F%20-%20Example%201%20(3).png)

- Finally, the ‘crosswise’ part. 
- Multiply diagonally and add the two products.

## Well done!

Thank you for completing our CPD course.
We hope you've enjoyed it and that it has given you some ideas for your own classroom.

[GIF: ](https://i.giphy.com/media/v1.Y2lkPTc5MGI3NjExNzNjYmVuY29hdGwyMHNycGFheGI0a29mNjA4ZGVtanF2ZTh0NTZ3OSZlcD12MV9pbnRlcm5hbF9naWZfYnlfaWQmY3Q9Zw/l0MYCn3DDRBBqk6nS/giphy.mp4)

## Test yourself on Method F - Vertical & Crosswise

[Practise this topic for free](https://app.senecalearning.com/classroom/course/d0e67498-99c8-47d2-ada7-cd629abed70c/section/59f8cc23-4bc5-4d8e-b5b4-c64d98191627/session)

- Previous topic: [3.1.5 Method E - Column Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-a-compendium-of-mathematical-methods-seneca-certified/3-1-5-method-e-column-method.md)

## CPD: A Compendium of Mathematical Methods (By Jo Morgan) contents

### 1 Course Overview
- 1.1 Course Structure & Commonly Asked Questions
  - [1.1.1 Introduction to the Course & Common Questions](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-a-compendium-of-mathematical-methods-seneca-certified/1-1-1-introduction-to-the-course-and-common-questions.md)

### 2 Subtraction: KS2/3
- 2.1 Subtraction Methods
  - [2.1.1 Method A - Decomposition Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-a-compendium-of-mathematical-methods-seneca-certified/2-1-1-method-a-decomposition-method.md)
  - [2.1.2 Method B - Equal Addition Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-a-compendium-of-mathematical-methods-seneca-certified/2-1-2-method-b-equal-addition-method.md)
  - [2.1.3 Method C - Expanded Form Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-a-compendium-of-mathematical-methods-seneca-certified/2-1-3-method-c-expanded-form-method.md)
  - [2.1.4 Method D - Partitioning Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-a-compendium-of-mathematical-methods-seneca-certified/2-1-4-method-d-partitioning-method.md)
  - [2.1.5 Method E - Counting-Up Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-a-compendium-of-mathematical-methods-seneca-certified/2-1-5-method-e-counting-up-method.md)
  - [2.1.6 Method F - Constant Difference Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-a-compendium-of-mathematical-methods-seneca-certified/2-1-6-method-f-constant-difference-method.md)
  - [2.1.7 Method G - Partial Differences Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-a-compendium-of-mathematical-methods-seneca-certified/2-1-7-method-g-partial-differences-method.md)
  - [2.1.8 Method H - Complementary Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-a-compendium-of-mathematical-methods-seneca-certified/2-1-8-method-h-complementary-method.md)
  - [2.1.9 Method I - Nines Complement Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-a-compendium-of-mathematical-methods-seneca-certified/2-1-9-method-i-nines-complement-method.md)

### 3 Expanding Double Brackets: KS3/4
- 3.1 Expansion Methods
  - [3.1.1 Method A - Grid Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-a-compendium-of-mathematical-methods-seneca-certified/3-1-1-method-a-grid-method.md)
  - [3.1.2 Method B - Each by Each](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-a-compendium-of-mathematical-methods-seneca-certified/3-1-2-method-b-each-by-each.md)
  - [3.1.3 Method C - Distributive Law](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-a-compendium-of-mathematical-methods-seneca-certified/3-1-3-method-c-distributive-law.md)
  - [3.1.4 Method D - Inspection](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-a-compendium-of-mathematical-methods-seneca-certified/3-1-4-method-d-inspection.md)
  - [3.1.5 Method E - Column Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-a-compendium-of-mathematical-methods-seneca-certified/3-1-5-method-e-column-method.md)
  - [3.1.6 Method F - Vertical & Crosswise](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-a-compendium-of-mathematical-methods-seneca-certified/3-1-6-method-f-vertical-and-crosswise.md)