28. Circle Theorems.

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Presentation transcript:

28. Circle Theorems

Circle Theorems Assumed knowledge recall the definition of a circle and identify (name) and draw the parts of a circle understand related terms of a circle draw a circle given the radius or diameter Reference material 10 Ticks MEP

Circle theorems learning objectives: find missing angles on diagrams (31.1 and rest of chapter) Reference Material 10 Ticks: MEP:

Circle theorems - Tangents learning objectives: understand and use the fact that the tangent at any point on a circle is perpendicular to the radius at that point (31.2) understand and use the fact that tangents from an external point are equal in length (31.2) give reasons for angle calculations involving the use of tangent theorems (31.2) Reference Material 10 Ticks: MEP:

Circle theorems learning objectives: Prove and use the facts that the angle subtended by an arc at the centre of a circle is twice the angle subtended at any point on the circumference (31.3) the angle in a semicircle is a right angle (31.3) the perpendicular from the centre of a circle to a chord bisects the chord (31.3) the angles in the same segment are equal (31.4) opposite angles in a cyclic quadrilateral sum to 180° (31.4) alternate segment theorem (31.4) Reference Material 10 Ticks: MEP:

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