What you need to know
Check yourself against these “I can” statements.
- I can find the midpoint of a line segment and the equation of its perpendicular bisector
- I can write down the equation of a circle and find its centre and radius by completing the square
- I can work out where a line meets a circle, including tangents
- I can use circle theorems, such as the angle in a semicircle, on a coordinate grid
Practise this topic
9 resourcesCircle Geometry
Coordinate geometry of circles in eleven levels: centre, radius and equation; completing the square; the equation from a diameter or a centre and a point; points inside, on or outside and the axis crossings; a line meeting a…
⚙️ WorksheetCircle Geometry Exam Questions
Multi-part exam-style questions on the coordinate geometry of circles, with marks for each part and each part building on the last: equations and intersections, diameters and tangents, chords and perpendicular bisectors, tangency…
⚙️ WorksheetCircles: Spot the Mistake
A student’s working with a mistake a real student would make (or, about 1 in 8 times, no mistake at all): tap the line you think is wrong, or No mistake, then reveal it, the corrected working and why. One level for each part of…
🧮 ToolCircle Explorer
Drag a circle’s centre and radius on a large coordinate grid and see its equation in both forms, with the working for completing the square (or type an equation in either form). Points inside, on or outside, shortest and longest…
⬢ BlockbustersCircle Geometry Blockbusters
Blockbusters with the questions from the Circle Geometry worksheet: choose its levels for the ordinary hexagons and for the harder ★ ones. Show the answer and the worked solution, or play against the computer with multiple choice.
📋 Unit reviewCircles: Exam Questions
Exam-style questions on the whole Circles chapter, researched from real papers, with mark schemes in the examination’s notation (M, A, B, dM, ft, cso and the AO codes): midpoints and perpendicular bisectors, equations of circles…
⬢ BlockbustersCircles: Spot the Mistake Blockbusters
Blockbusters with the questions from the Circles: Spot the Mistake worksheet: choose its levels for the ordinary hexagons and for the harder ★ ones. Show the answer and the worked solution, or play against the computer with…
🧩 ConnectionsCoordinate Geometry
Straight lines and circles, each described four different ways: equations, gradient and points, parallel or perpendicular conditions, centres, radii and diameters.
🧮 ToolGraph Plotter
A graphing calculator: type y = f(x), x = g(y), implicit relations such as x² + y² = 25, inequalities (shaded, dashed for < and solid for ≤), parametric and polar curves, points and tables, functions f(x) = … with f′(x), and…
Topics in this unit
- 6.2 Equation of a circle · 1 resource
These are the pages for Circles in the A Level Maths scheme of work, following Pearson Edexcel A Level Mathematics (9MA0). Open this topic in Mr Wells Maths to see it alongside the rest of the course.