Mathematics / Year 7 / Algebra

Curriculum content descriptions

recognise and use variables to represent everyday formulas algebraically and substitute values into formulas to determine an unknown (AC9M7A01)

Elaborations
  • linking variables to attributes and measures being modelled when using formulas, such as the area of a rectangle is equal to the length x width as \(A\;=\;l\;\times\;w\) or using \(p\;=\;6g\;+\;b\) to describe a total of points expressed as goals (worth \(6\) points) and behinds (worth one point)
  • interpreting and using formulas obtained from other sources; for example, maximum heart rates and target heart rates for moderate exercise
  • substituting numerical values for variables when using formulas and calculating the value of an unknown in practical situations; for example, calculating weekly wage \(W\) given base wage \(b\) and overtime hours \(h\) at \(1.5\) times rate \(r\), \(W\;=\;b+1.5\times h\times r\), using values for mass \(m\) and volume \(v\) to determine density \(d\) of a substance where \(d\;=\;\frac mv\)
  • using everyday formulas and their application to contexts on Country/Place, investigating the relationships between variables
General capabilities
  • Critical and creative thinking Critical and Creative Thinking
  • Numeracy Numeracy
ScOT terms

Substitution,  Variables (Mathematics),  Equations

Video

Patterns, primes and Pascal's Triangle

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Video

Algebra basics video

Use this video as a springboard to introduce algebraic thinking, and to apply that thinking to a financial context, drawing on reasoning.

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

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MathXplosion, Ep 1: Magic 9s

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Catalyst: Probability and the birthday paradox

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Catalyst: Small scale measurements

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Working out the areas

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The amazing 'angle-a-tron'

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MathXplosion, Ep 33: On the grid

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Video

MathXplosion, Ep 17: Develop mathematical mind-reading skills

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Catalyst: Probability and the gambler's fallacy

Mathematician Lily Serna visits Luna Park to explain a great probability pitfall. She shares a century-old tale from Monte Carlo casino, and then she puts its lesson to the test. If you flip a coin and it lands on heads three times in a row, what result would you predict for the next flip? Find out why intuition might land ...

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MathXplosion, Ep 11: Fun facts about the number seven

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Video

Catalyst: Prime numbers and unbreakable codes

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Video

What are pixels?

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Video

BTN: What is the GST?

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Numbers Count: What are factors?

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MathXplosion, Ep 6: Zero the hero

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Area of a square and a triangle

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Video

Modelling climate changes

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Video

Catalyst: Take the Phi Golden challenge

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