Coaching Centre
Chapter 6: Circle geometry Notes
Extension: circle terminology, chord properties, angles at the centre and circumference, angles in the same segment and semicircle, cyclic quadrilaterals, tangents and the alternate segment theorem, and intersecting chords, secants and tangents.
Sections
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6A Circle terms and chord properties Mastered
Naming parts of a circle, the perpendicular from the centre bisects a chord, and equal chords are equidistant from the centre.
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6B Angle properties of circles Mastered
The angle at the centre is twice the angle at the circumference, angles in the same segment are equal, and the angle in a semicircle is a right angle.
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6C Cyclic quadrilaterals Mastered
Opposite angles of a cyclic quadrilateral are supplementary, and the exterior angle equals the interior opposite angle.
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6D Tangents Mastered
A tangent is perpendicular to the radius at the point of contact, tangents from an external point are equal, and the alternate segment theorem.
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6E Intersecting chords, secants and tangents Mastered
Products of intercepts for intersecting chords, two secants from an external point, and a secant and a tangent (the square of the tangent).