Mathematics / Year 7 / Measurement and Geometry / Geometric reasoning

Curriculum content descriptions

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

Elaborations
  • using concrete materials and digital technologies to investigate the angle sum of a triangle and quadrilateral
General capabilities
  • Numeracy Numeracy
ScOT terms

Polygons,  Adjacent angles

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Numeracy wrap: Tell me why

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

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The geometer's warehouse

This web-based, multimedia resource focuses on the geometry of the Stage 4 and Stage 5 Mathematics syllabus. It comprises 70 dynamic html worksheets, each exploring a different outcome in Stage 4 and Stage 5 geometry.

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The Geometry and Algebra of Honeycomb - Calculate

This integrated unit of work explores the amazing structures of honeycomb by examining the properties of regular and irregular polygons and polyhedra. Students then move on to solve problems using geometric and algebraic reasoning.

Video

MathXplosion, Ep 50: How to use a tetrahedron to solve the tree problem

How can you place four trees exactly the same distance apart from one other? By making a model! By using miniature trees to make a model of the problem, it becomes clear that a 2D solution is impossible. We learn how objects can help us visualise the problem situation, which in this case requires a 3D solution: a tetrahedron.

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MathXplosion, Ep 10: What is the strongest shape?

Are triangles really the strongest shapes ever? If so, why? Learn how and why right-angled and equilateral triangles have been used in engineering, architecture and design through the ages.

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Maths inside bees and beehives

Bees are necessary for assisting many plants to produce the food we eat, including meat and milk. Colony collapse disorder, which describes the disappearance of beehives, could have catastrophic effects on food production. Australian scientists are applying their maths and science knowledge to build up a picture of a healthy ...

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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 ...

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Modelling climate changes

There is a saying: 'climate is what you expect and weather is what you get'. |Understanding climate change is very difficult for most people, especially when the weather we experience is different from the information we are given by scientists about the climate changing. The difference is that weather reflects short-term ...

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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.

Online

TIMES Module 13: Measurement and Geometry: construction - teacher guide

This is a 30-page guide for teachers that explains the central role of construction and presents examples of constructions.

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Numeracy wrap: Race across transversals

Interactive activities that guide students to explore angles in parallel lines.

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Examples of Pythagoras' Theorem Part 1

An animated tutorial demonstrating the application of Pythagoras' theorem through some worked examples, followed by a interactive quiz.

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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).

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Numeracy wrap: Parallelogram peculiarities

Interactive activities that guide students to investigate properties of parallelograms.

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Numeracy wrap: It's what's inside that counts

interactive activities that guide students to explore the interior and exterior angle sums of polygons.

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Renovate, Calculate!

A student resource that explores the use of mathematics in the trades. Highly interactive investigations into ratio, areas of special quadrilaterals and right-angled trigonometry.

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Are plants mathematicians?

Ever noticed that plants are examples of Fibonacci numbers? Watch Vi Hart draw examples of flower petals and leaf growth that follow this pattern. See how plants seem to use Phi (.), the golden ratio. Find out how to make your own 'angle-a-tron' to create interesting petal designs. This is the second in a series of two.

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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 ...

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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 ...

Online

TIMES Module 10: Measurement and Geometry: introduction to measurement - teacher guide

This is a 16-page guide for teachers. It provides an introduction to the initial ideas of measurement, and introduces the measurement of length, area, volume and time.