Mathematics / Year 9 / Number and Algebra / Real numbers

Curriculum content descriptions

Solve problems involving direct proportion. Explore the relationship between graphs and equations corresponding to simple rate problems (ACMNA208)

Elaborations
  • identifying direct proportion in real-life contexts
General capabilities
  • Literacy Literacy
  • Numeracy Numeracy
  • Critical and creative thinking Critical and creative thinking
ScOT terms

Rates (Ratios),  Linear equations,  Direct proportions,  Gradients

Interactive

Syllabus Bites: Revisiting proportion

This is the first in a series of Syllabus Bites related to direct and indirect proportion. Students revise the concept of ratio. They create short visual explanations showing how problems can be solved.

Interactive

Syllabus Bites: Direct proportion

This is the second in a series of Syllabus Bites related to direct and indirect proportion. Interactive applets and dynamic geometry software allow students to explore quantities in direct proportion. Students draw conclusions about relationships between the variables and consolidate their understanding by playing a simple game.

Interactive

Syllabus Bites: Graphing direct proportion

This is the third in a series of Syllabus Bites related to direct and indirect proportion. Students draw graphs to represent relationships between variables in direct proportion. They associate the gradient of the graph with the constant of proportionality. They investigate practical contexts that give rise to direct proportion.

Video

Catalyst: Nautical Robots

How might you find out how much and where the Earth's oceans are warming? Watch the report by Ruben Meerman and discover how more than 3000 'nautical robots', known as argo floats, have been placed in the oceans to collect data on variations in temperature, pressure and salinity.

Downloadable

Different ways to pay

This lesson challenges students to explore the pros and cons of various payment options, how they spend their money, different consumer products and where to go for more information about saving money and debt. During the lesson, students investigate multiple payment options to choose those that suit their circumstances, ...

Interactive

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.

Interactive

The Numberline

An interactive tool that can help students explore a number line, including points representing integers, fractions and decimals

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 ...

Online

TIMES Module 32: Number and Algebra: fractions and the index laws in algebra - teacher guide

This is a 24-page guide for teachers. This module extends the use of pronumerals to include algebraic fractions. It includes substitution, adding like terms, the use of brackets and multiplying terms, the use of algebra to describe number patterns and extending the use of the index laws. Algebraic notation is discussed.

Video

Catalyst: Graham's number

If you were asked what the biggest number you can think of is, what would you say? Infinity? Well, what about the biggest finite number you can think of? Mathematician Ron Graham came across such a gigantic number in his research that, to capture its massive size, he and his colleagues needed to come up with new methods ...

Online

TIMES Module 21: Number and Algebra: rates and ratios - teacher guide

This is a 17-page guide for teachers. This module introduces the idea of ratios and rates. Ratios are used to compare two quantities. The emphasis is usually on comparing parts of the whole. Rates are a measure of how one quantity changes for every unit of another quantity. It relates the ideas of ratios, gradient and fractions.

Video

Stateline: Mapping farmland: using area and trigonometry

In northern Queensland's Gulf region, some farmers use GPS mapping to help manage their extensive properties. Use this clip as a context for applying your understanding of area, in particular your understanding of conversion between square kilometres and hectares. Apply trigonometry and Pythagoras' theorem.

Interactive

Simultaneous Equations: animation

A short animated introduction to simultaneous equations and a demonstration of the elimination method of solution, followed by an interactive quiz.

Interactive

Desmos Graphing Calculator - Google Play app

Plot functions, create tables, add sliders and animate your graphs. Touch points of interest on the graph to show maximums, minimums and points of intersection. Type in an equation and watch the calculator solve the problem. Free when reviewed on 12/5/2015.

Video

My Five Cents: What is opportunity cost?

What is the true cost of buying something? Gen Fricker explains that it's more than just money. Learn about opportunity cost - what it is, why it's a helpful tool and when to use it. Simple! Then test yourself with ASIC MoneySmart's "Things to think about" classroom exercises.  

Video

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.

Video

Big data, better hospitals

Overcrowding in hospitals is one of the biggest challenges facing our healthcare system . In order to reduce hospital waiting times, the Patient Admission Prediction Tool (PAPT) uses historical data to predict how many patients, and with what kinds of injuries, are expected to arrive at the emergency department each day ...

Video

Mystery man Pythagoras meets his match

What do you know about Pythagoras? Join Vi Hart as she not only explains his theorem but raises some legends about his dark past! Follow Vi's timeline of famous mathematicians to find out in which century Pythagoras lived. See how Vi shows a proof of his theorem and raises what was a big dilemma for Pythagoras: the irrational ...

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.

Video

My Five Cents: Why investing can be risky

Planning to get rich quick by investing one day? Before you jump in, let Gen Fricker explain some of the risks involved with different types of investments. Then test yourself with ASIC MoneySmart's "Things to think about" classroom exercises.