AC9M7M05

See also: Learning Areas / Mathematics / Mathematics / Measurement / Year 7

demonstrate that the interior angle sum of a triangle in the plane is 180° and apply this to determine the interior angle sum of other shapes and the size of unknown angles

Elaborations

• AC9M7M05_E1 - using concrete materials to demonstrate that the sum of the interior angles of a triangle is 180°; for example, using paper triangles and tearing to demonstrate that the interior angles when combined form 180°
• AC9M7M05_E2 - using decomposition and the angle sum of a triangle to generalise the interior angle sum of an \(n\)-sided polygon, as \(180(n-2)\;=\;180n-360\)

Achievement Standard Components

• ASMAT710 - They apply knowledge of angle relationships and the sum of angles in a triangle to solve problems, giving reasons.