# Corresponding Angles and Alternate Angles Worksheets and Revision

GCSE 4 - 5KS3AQAEdexcelOCRWJECFoundationAQA 2022Edexcel 2022OCR 2022WJEC 2022

## Corresponding and Alternate Angles: 4 Simple Rules

Corresponding and alternate angles are formed when a straight line passes through two parallel lines.

Parallel means that two lines are always the same distance away from each other,  and therefore will never meet. Parallel lines are marked with matching arrows as shown in the examples below.

Drawing a straight line that passes through two parallel lines creates a whole bunch of angles that are all related to each other. How these angles are related is explained by 4 simple rules.

Level 4-5 GCSE

## Alternate Angles:

Alternate angles are the same.

$\textcolor{red}{D} = \textcolor{skyblue}{C}$

They are found in a Z-shape, and sometimes called “Z angles

Level 4-5 GCSE

## Corresponding Angles

Corresponding angles are the same.

$\textcolor{orange}{F} = \textcolor{blue}{E}$

They are found in an F-shape and are sometimes called “F angles

Level 4-5 GCSE

## Vertically aligned angles

Vertically aligned angles are the same

$\textcolor{limegreen}{A} = \textcolor{purple}{B}$

These are often called “vertically opposite angles“.

Level 4-5 GCSE

## Interior / Allied angles

Allied angles add up to $180\degree$

$\textcolor{maroon}{H} + \textcolor{green}{G} = 180\degree$

These can be refereed to as either Allied angles or Interior angles.

Level 4-5 GCSE

## Example: Angles in Parallel Lines

Find the angle marked $x$ in the picture below.

$BD$ and $EG$ are parallel lines.

State which angle rule you used at each step.

[2 marks]

Currently we cannot see a rule connecting $\angle EFC$ with $x$

This means we will need multiple steps.

Firstly, we will use the fact that angles on a straight line add to $180$ degrees.

Specifically, $\angle EFC$ and $\angle CFG$ add to make $180\degree$.

Which means we can do the following:

$\angle CFG = 180\degree - 32\degree = 148\degree$.

Now, looking at the diagram we can see that angle $\angle CFG$ and the missing angle $x$ are corresponding angles.

Therefore, we get

$x = 148\degree$.

As mentioned, there are multiple ways to do this question.

Level 4-5GCSE

## Example Questions

Using corresponding angles, we find that $\angle \text{AHB} = \angle \text{FGH}$, so $\angle x = 37\degree$

First identifying that $\angle \text{FGH}$  and  $\angle \text{GHC}$ are alternate angles, we get

$\angle \text{GHC}=41\degree$

Then as $\text{BE}$ is a straight line we can use the fact that angles on a straight line sum to $180\degree$,

$x=180\degree-41\degree=139\degree$

Firstly, because angle HFG and angle EFC are vertically opposite, we get

$\angle \text{EFC} = 48\degree$

Secondly, because angle EFC and angle BCA ($\angle x$) are corresponding angles, we get

$\angle \text{BCA} = x = 48\degree$

Firstly, using the fact that angles FGJ and CDG are corresponding angles, we get

$\angle \text{CDG } = 121\degree$

Secondly, because angles on a straight line add to $180\degree$, and angles CDG and CDA are on a straight line,

$\angle \text{CDA } = 180 - 121 = 59\degree$

Thirdly, again using the fact that angles on a straight line add to $180\degree$, and angles CDA, BDE, and ADB (otherwise known as angle $x$) are on a straight line, we get

$x + 50 + 59 = 180,\text{ so } x = 180 - 109 = 71\degree$

Firstly, because angles BEF and EHJ are corresponding angles, we get

$\text{angle EHJ } = 39\degree$.

Next, because angles EDH and DHG are alternate angles, we get

$\text{angle DHG } = 76\degree$.

Then, because angles DHG, DHE, and EHJ are angles on a straight line and angles on a straight line add to $180\degree$, we get

$\text{angle DHE } = 180 - 76 - 39 = 65\degree$

Finally, because angle DHE and angle $x$ are vertically opposite angles, we get

$x = 65\degree$.

There are other possible methods for doing this question. As long as you’ve correctly applied angle fact, explained each step, and got the answer to be $71\degree$, your answer is correct.

## Worksheet and Example Questions

### (NEW) Parallel lines Exam Style Questions - MME

Level 1-3 Level 4-5 GCSENewOfficial MME

Level 4-5 GCSE

## You May Also Like...

### GCSE Maths Revision Cards

Revise for your GCSE maths exam using the most comprehensive maths revision cards available. These GCSE Maths revision cards are relevant for all major exam boards including AQA, OCR, Edexcel and WJEC.

£8.99

### GCSE Maths Revision Guide

The MME GCSE maths revision guide covers the entire GCSE maths course with easy to understand examples, explanations and plenty of exam style questions. We also provide a separate answer book to make checking your answers easier!

From: £14.99