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Maths
6 Dec 2025
92
5 pages
Quadrilaterals are everywhere around you - from your phone screen to football pitches! Understanding these four-sided shapes and... Show more
Every quadrilateral is simply a shape with four sides, but they all share some important features. You'll find that all quadrilaterals have exactly 4 sides and their internal angles always add up to 360ยฐ.
Most quadrilaterals contain parallel lines - these are lines that never meet, like railway tracks. Squares and rectangles are special types of quadrilaterals because they have 4 right angles (90ยฐ each).
Quick Check Look around your classroom right now - can you spot at least three quadrilaterals? Your desk, the whiteboard, and even the windows are probably quadrilaterals!
These shapes aren't just for maths lessons - architects, designers, and engineers use quadrilaterals to create everything from buildings to video games.
Working out the area of rectangles and squares is straightforward once you know the magic formula. The formula is simply base ร height (or length ร width).
Let's tackle this step by step if you have a rectangle that's 4cm wide and 10cm tall, you multiply 4 ร 10 = 40. Therefore, the area is 40cmยฒ.
Top Tip Always remember to include cmยฒ (square centimetres) in your answer - it shows you're measuring area, not just length!
This formula works for any rectangle or square, making it one of the most useful maths skills you'll learn.
Here's another example to build your confidence with the base ร height formula. When you see a rectangle measuring 7cm by 11cm, you simply multiply these numbers together.
Following our trusty formula 7 ร 11 = 77, which means the area is 77cmยฒ. Notice how the process stays exactly the same regardless of the numbers involved.
Remember It doesn't matter which measurement you call the base and which you call the height - multiplication works the same way round!
Practice with different sized rectangles will make this calculation feel completely natural.
Let's try one more example to cement your understanding. This rectangle measures 12cm by 8cm, so we apply our reliable formula once again.
Using base ร height 12 ร 8 = 96, giving us an area of 96cmยฒ. You're probably noticing how straightforward this becomes with practice.
Confidence Booster You've now mastered the area formula for rectangles and squares - this skill will help you in geometry, design technology, and even real-life situations like measuring rooms!
The key is remembering that formula and always including the correct units in your final answer.
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
You can download the app from Google Play Store and Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help โ all at your fingertips.
3
Smart Tools NEW
Transform this note into: โ 50+ Practice Questions โ Interactive Flashcards โ Full Mock Exam โ Essay Outlines
Explore the detailed mark scheme for the OCR GCSE Higher Mathematics Paper 6 from June 2018. This resource covers key concepts such as triangle congruence, vector addition, area calculations, and more, providing essential guidance for exam preparation and understanding of marking criteria.
MathsExplore essential trigonometry concepts including formulas for sine, cosine, and tangent. Learn how to find angles and side lengths in right triangles using trigonometric ratios and inverse functions. This summary is perfect for students preparing for exams or needing a quick reference on trigonometric principles.
MathsExplore the fundamentals of bearings in geometry, including angle measurement, relationships, and rules. This summary covers key concepts such as calculating bearings, angle pairs, and the total angles in triangles. Ideal for students preparing for exams or seeking to enhance their understanding of geometry.
MathsPrepare for your GCSE exams with this comprehensive non-calculator practice paper. Covering key concepts such as area of triangles, ratios, statistical averages, and more, this resource includes 22 questions with varying marks to help you master essential mathematical skills. Ideal for students aiming for higher grades, this practice paper is designed to enhance your problem-solving abilities and exam readiness.
MathsExplore essential circle theorems, including properties of inscribed quadrilaterals, central angles, and angle bisectors. This summary covers key concepts such as congruent chords, angles subtended by arcs, and the relationship between tangents and radii. Ideal for quick revision and understanding of circle geometry.
MathsExplore the fundamentals of bearings in geometry, including how to measure angles accurately and the importance of using three digits. This summary covers key concepts such as angle relationships and measurement techniques, essential for mastering this topic in your studies.
MathsQuotes from every main character
English LiteratureApp Store
Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because itโs too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH ๐๐๐ฒ๐ค๐โจ๐๐ฎ
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because itโs too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH ๐๐๐ฒ๐ค๐โจ๐๐ฎ
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
Quadrilaterals are everywhere around you - from your phone screen to football pitches! Understanding these four-sided shapes and how to calculate their areas is a fundamental maths skill you'll use constantly.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Every quadrilateral is simply a shape with four sides, but they all share some important features. You'll find that all quadrilaterals have exactly 4 sides and their internal angles always add up to 360ยฐ.
Most quadrilaterals contain parallel lines - these are lines that never meet, like railway tracks. Squares and rectangles are special types of quadrilaterals because they have 4 right angles (90ยฐ each).
Quick Check: Look around your classroom right now - can you spot at least three quadrilaterals? Your desk, the whiteboard, and even the windows are probably quadrilaterals!
These shapes aren't just for maths lessons - architects, designers, and engineers use quadrilaterals to create everything from buildings to video games.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Working out the area of rectangles and squares is straightforward once you know the magic formula. The formula is simply base ร height (or length ร width).
Let's tackle this step by step: if you have a rectangle that's 4cm wide and 10cm tall, you multiply 4 ร 10 = 40. Therefore, the area is 40cmยฒ.
Top Tip: Always remember to include cmยฒ (square centimetres) in your answer - it shows you're measuring area, not just length!
This formula works for any rectangle or square, making it one of the most useful maths skills you'll learn.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Here's another example to build your confidence with the base ร height formula. When you see a rectangle measuring 7cm by 11cm, you simply multiply these numbers together.
Following our trusty formula: 7 ร 11 = 77, which means the area is 77cmยฒ. Notice how the process stays exactly the same regardless of the numbers involved.
Remember: It doesn't matter which measurement you call the base and which you call the height - multiplication works the same way round!
Practice with different sized rectangles will make this calculation feel completely natural.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Let's try one more example to cement your understanding. This rectangle measures 12cm by 8cm, so we apply our reliable formula once again.
Using base ร height: 12 ร 8 = 96, giving us an area of 96cmยฒ. You're probably noticing how straightforward this becomes with practice.
Confidence Booster: You've now mastered the area formula for rectangles and squares - this skill will help you in geometry, design technology, and even real-life situations like measuring rooms!
The key is remembering that formula and always including the correct units in your final answer.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
You can download the app from Google Play Store and Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help โ all at your fingertips.
3
Smart Tools NEW
Transform this note into: โ 50+ Practice Questions โ Interactive Flashcards โ Full Mock Exam โ Essay Outlines
Explore the detailed mark scheme for the OCR GCSE Higher Mathematics Paper 6 from June 2018. This resource covers key concepts such as triangle congruence, vector addition, area calculations, and more, providing essential guidance for exam preparation and understanding of marking criteria.
MathsExplore essential trigonometry concepts including formulas for sine, cosine, and tangent. Learn how to find angles and side lengths in right triangles using trigonometric ratios and inverse functions. This summary is perfect for students preparing for exams or needing a quick reference on trigonometric principles.
MathsExplore the fundamentals of bearings in geometry, including angle measurement, relationships, and rules. This summary covers key concepts such as calculating bearings, angle pairs, and the total angles in triangles. Ideal for students preparing for exams or seeking to enhance their understanding of geometry.
MathsPrepare for your GCSE exams with this comprehensive non-calculator practice paper. Covering key concepts such as area of triangles, ratios, statistical averages, and more, this resource includes 22 questions with varying marks to help you master essential mathematical skills. Ideal for students aiming for higher grades, this practice paper is designed to enhance your problem-solving abilities and exam readiness.
MathsExplore essential circle theorems, including properties of inscribed quadrilaterals, central angles, and angle bisectors. This summary covers key concepts such as congruent chords, angles subtended by arcs, and the relationship between tangents and radii. Ideal for quick revision and understanding of circle geometry.
MathsExplore the fundamentals of bearings in geometry, including how to measure angles accurately and the importance of using three digits. This summary covers key concepts such as angle relationships and measurement techniques, essential for mastering this topic in your studies.
MathsQuotes from every main character
English LiteratureApp Store
Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because itโs too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH ๐๐๐ฒ๐ค๐โจ๐๐ฎ
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because itโs too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH ๐๐๐ฒ๐ค๐โจ๐๐ฎ
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
Sociology