The Equation of a Circle

Curriculum support15 minsFREE

Key takeaways
Understand the general equation of a circle is in the form x²+y²=r².
Use the equation of a circle to find the radius of a circle or draw a circle on an axis.
Show that a set of coordinates lie on the circumference of a circle.
Shahriyar HajghassemHost: Shahriyar is a Maths Teacher at a School in Northwest London, teaching years 7 to 11. He graduated from the University of Warwick in 2013 and set off to China for two years teaching IGCSE and A-Level Economics.

Circles are a big part of maths, so feeling confident with them is important! In this lesson, students will learn how to find the equation of a circle using Pythagoras’ theorem. Students will also learn to write the equation of a circle in its general form. This class is aimed at students in Years 9-11 and is a grade 6 topic for students sitting the higher GCSE paper, however often the equation of a circle can be incorporated into more complex problem-solving questions.

Learn more about circles: Parts of a CircleCircumference of a Circle & SectorArea of a Circle & Sector


Safeguarding reminder:The safety of your child is of the utmost importance. All of our classes are pre-recorded to remove any concerns around live participation. For reruns of our past live classes, students' webcams and microphones were disabled and only the chat history, if participation was requested, is visible.

Suitable for:

This class is suitable for students in Years 9 - 11.

Class requirements:
You will need a laptop or device with internet connection to watch the class, as well as a pen and notepad for taking notes.
What to expect:
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