Support · Stage 5 · Properties of geometrical figures B (Path)
Support Apply the result for the sum of the interior angles of a triangle to find, by dissection, the sum of the interior angles of a polygon with more than 3 sides
Resources for the prerequisite content of this dot point: earlier-stage (or earlier sub-level) dot points in the same strand that students usually need first. Use these to fill gaps before or alongside the core lesson.
Prerequisite links are draft mappings generated from the syllabus structure (earlier stage, same strand, closest content). They are being reviewed by teachers. Spot a poor match? Tell us.
Prerequisite dot points
Prove that the interior angle sum of a triangle is 180° with or without digital tools
Stage 4 · Properties of geometrical figures Draft mapping
- Interactive toolEnrichmentDesmos GeometryUse it for: Construct and drag figures to test angle conjectures.
- Interactive toolEnrichmentGeoGebra ClassicUse it for: Dynamic geometry and graphing for constructions and proofs.
- Corbettmaths practice questions: Angles: full circle (at a point)Use it for: Free printable graded practice questions (with answers) on angles: full circle (at a point) for drill or a quick check.
- WorksheetDrillKuta free worksheet: Angle sum of triangles and quadrilateralsUse it for: Printable skills-practice sheet with answer key on angle sum of triangles and quadrilaterals; good for drill or homework.
- WorksheetDrillKuta free worksheet: Triangle angle sumUse it for: Printable skills-practice sheet with answer key on triangle angle sum; good for drill or homework.
- VideoStarterCorbettmaths video: Angles: triangleUse it for: Short worked-example video on angles: triangle to model the method before practice or for flipped revision.
- VideoStarterEddie Woo (WooTube): Basic Properties of Geometrical Figures playlistUse it for: Sydney teacher Eddie Woo's recorded lessons on properties of geometrical figures; play a clip to model a method or for revision.
Prove that any exterior angle of a triangle equals the sum of the 2 interior opposite angles
Stage 4 · Properties of geometrical figures Draft mapping
- WorksheetDrillKuta free worksheet: The exterior angle theoremUse it for: Printable skills-practice sheet with answer key on the exterior angle theorem; good for drill or homework.
- VideoStarterEddie Woo (WooTube): Basic Properties of Geometrical Figures playlistUse it for: Sydney teacher Eddie Woo's recorded lessons on properties of geometrical figures; play a clip to model a method or for revision.
Apply the angle sum of a triangle to prove that the angle sum of a quadrilateral is 360°
Stage 4 · Properties of geometrical figures Draft mapping
- Corbettmaths practice questions: Angles: full circle (at a point)Use it for: Free printable graded practice questions (with answers) on angles: full circle (at a point) for drill or a quick check.
- WorksheetDrillKuta free worksheet: Angle sum of triangles and quadrilateralsUse it for: Printable skills-practice sheet with answer key on angle sum of triangles and quadrilaterals; good for drill or homework.
- WorksheetDrillKuta free worksheet: Angles in quadrilateralsUse it for: Printable skills-practice sheet with answer key on angles in quadrilaterals; good for drill or homework.
- VideoStarterCorbettmaths video: Angles: quadrilateralsUse it for: Short worked-example video on angles: quadrilaterals to model the method before practice or for flipped revision.