Mathematics A-Level
circle equation
What circle equation means in Mathematics A-Level, as defined for WJEC.
Definition of circle equation
Check what you remember
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Reference: WJEC
The locus of all points (x, y) at a fixed radius r from a centre (a, b), written as (x − a)² + (y − b)² = r².
Topics that use circle equation
Related terms
- angle in a semicircle
- linear modelling
- perpendicular bisector of chord
- point-slope form
- rate of change
- tangents and normals
- centre and radius
- completing the square for circles
Using circle equation in the exam
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