Understand and apply the symmetry properties of circles, including that equal chords are at the same distance from the center, the perpendicular bisector of a chord goes through the center, and that tangents drawn from a point outside the circle are of equal length. Use these properties to justify answers in geometrical problems.

Quick explanation

Understand and apply the symmetry properties of circles, including that equal chords are at the same distance from the center, the perpendicular bisector of a chord goes through the center, and that tangents drawn from a point outside the circle are of equal length. Use these properties to justify answers in geometrical problems

• This point belongs to Circle theorems II, especially Circle theorems II outcomes.
• You need to be able to understand and apply the symmetry properties of circles, including that equal chords are at the same distance from the center, the perpendicular bisector of a chord goes through the center, and that tangents drawn from a point outside the circle are of equal length. Use these properties to justify answers in geometrical problems.
• The key ideas to know are Explain, State, and Describe.
• Use the linked flashcards and practice questions to check recall, then practise applying the idea in an exam-style answer.