Mathematics / Year 7 / Measurement

Curriculum content descriptions

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 (AC9M7M05)

Elaborations
  • 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 \(180\)°
  • using decomposition and the angle sum of a triangle to generalise the interior angle sum of an \(n\)-sided polygon, as \(180(n-2)\;=\;180n-360\)
General capabilities
  • Numeracy Numeracy
ScOT terms

Interior angles,  Polygons

Refine by year level


Refine by learning area


Refine by topic

Related topic
Interactive

Numeracy wrap: Tell me why

Interactive activities that guide students to consider the use and presentation of geometric reasoning.

Video

MathXplosion, Ep 34: Kite symmetry

Unfurl the secret of symmetry used in kites to make them fly! A kite in geometry looks a lot like a kite in the sky. We see that a kite is a special quadrilateral in which one of its two diagonals (long and short) is also its axis of symmetry, and if you fold the kite along that diagonal, the two halves will match up exactly ...

Video

Area of a square and a triangle

Do you know the formula for working out the area of a square? How about a triangle? Watch this short maths video to learn the formulas for both.

Video

Working out the areas

Do you know how to work out the area of a square, a rectangle or a triangle? Learn the simple maths formulas needed from this video. What would be the area of a rectangle with a height of 5cm and a length of 3cm?

Text

Tessellating tiles

In this teaching resource students learn how to construct shapes that will tessellate (or tile) a plane area. Starting with a regular shape known to tessellate (square, equilateral triangle, hexagon), students apply geometrical transformations to the sides of the shape to create new shapes that tessellate. There are links ...

Interactive

Area of a parallelogram

This is a Geogebra activity used to teach the area of a parallelogram. Suitable for use with an interactive whiteboard (IWB).

Interactive

Numeracy wrap: Parallelogram peculiarities

Interactive activities that guide students to investigate properties of parallelograms.

Interactive

The Mathematical Toolkit

A 2D Shapes tool that can be used to create geometric objects such as quadrilaterals, circles, triangles, lines, arcs, rays, segments and vectors on a coordinate grid. Plot and label the vertices to reveal the internal angles, side lengths, area and perimeter, then manipulate the shapes on a grid to transform their shape ...

Downloadable

Measurement: Foundation to Year 9

This comprehensive resource describes the progression of measurement ideas. The resource demonstrates examples of relevant teaching strategies, investigations, activity plans and connected concepts in measurement including teaching and cultural implications.