Properties of Geometrical Figures 1
Outcomes

Classify triangles according to their side and angle properties and describe quadrilaterals (ACMMG165)

Recognise and classify types of triangles on the basis of their properties (acuteangled triangles, rightangled triangles, obtuseangled triangles, equilateral triangles, isosceles triangles and scalene triangles)
Examples

Investigate the properties of special quadrilaterals (parallelograms, rectangles, rhombuses, squares, trapeziums and kites), including whether: the opposite sides are parallel, the opposite sides are equal, the adjacent sides are perpendicular, the opposi
Examples

Recognise and classify types of triangles on the basis of their properties (acuteangled triangles, rightangled triangles, obtuseangled triangles, equilateral triangles, isosceles triangles and scalene triangles)
 Identify line and rotational symmetries (ACMMG181)

Demonstrate that the angle sum of a triangle is 180 degrees and use this to find the angle sum of a quadrilateral (ACMMG166)

Justify informally that the interior angle sum of a triangle is 180 degrees, and that any exterior angle equals the sum of the two interior opposite angles
Examples

Use the angle sum results for triangles and quadrilaterals to determine unknown angles in triangles and quadrilaterals, giving reasons
Examples

Justify informally that the interior angle sum of a triangle is 180 degrees, and that any exterior angle equals the sum of the two interior opposite angles
 Use the properties of special triangles and quadrilaterals to solve simple numerical problems with appropriate reasoning