Mathematics / Year 9 / Measurement and Geometry / Geometric reasoning

Curriculum content descriptions

Solve problems using ratio and scale factors in similar figures (ACMMG221)

Elaborations
  • establishing the relationship between areas of similar figures and the ratio of corresponding sides (scale factor)
General capabilities
  • Literacy Literacy
  • Numeracy Numeracy
  • Critical and creative thinking Critical and creative thinking
ScOT terms

Ratios,  Scale (Proportions),  Similarity (Geometry)

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Mathematics of bushfire

In these classroom activities students will be introduced to some of the basic mathematical principles that underpin wildfire science, with an emphasis on how theoretical concepts are used to aid our understanding of the real world, and bushfire in particular. They will learn about the complexities of the fire management ...

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Work sample Year 9 Mathematics: Similar triangles

This work sample demonstrates evidence of student learning in relation to aspects of the achievement standards for Year 9 Mathematics. The primary purpose for the work sample is to demonstrate the standard, so the focus is on what is evident in the sample not how it was created. The sample is an authentic representation ...

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Mathematical modelling (Measurement): Year 9 – planning tool

This planning resource for Year 9 is for the topic of Mathematical modelling. Students continue to solve mathematical problems from the real world around them. They draw upon knowledge learnt in the area of Measurement.

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Pythagoras and trigonometry (Measurement): Year 9 – planning tool

This planning resource for Year 9 is for the topic of Pythagoras and trigonometry. Students apply and build upon knowledge of Pythagoras’ theorem, angle properties, trigonometry and scales to solve problems involving right-angled triangles.

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A Little Atmosphere

This activity invites students to model the scaled thickness of the atmosphere on a globe using sheets of transparency material. The activity includes a list of tools and materials required, what to do and notice, an explanation for the underlying science of what students observe and suggestions for further activities.

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Volume of a Pyramid and a Cone

This resource is a web page containing an investigative task to explore volume. Derive the formulae for the volumes of a square-based pyramid and a cone, using mathematical concepts. A printable resource is also available to support the task. This resource is an activity from the NRICH website.

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In a spin

This resource is a web page containing a short task to explore volume of a solid shape. The task involves calculating the volume of the solid formed by rotating a right angled triangle about its hypotenuse A printable resource and solution is also available to support the task. This resource is an activity from the NRICH ...

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Indigo Interior

This resource is a web page containing a problem solving task that requires an understanding of Pythagoras' theorem. The task involves finding the area of shaded region with a circle with a known area. To solve the problem students need to establish a right angled triangle and apply Pythagoras' theorem. A printable resource ...

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Simple interest

This is a website designed for both teachers and students that addresses simple interest from the Australian Curriculum for year 9 students. It contains material on calculating simple interest. There are pages for both teachers and students. The student pages contain interactive questions for students to check their progress ...

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Scientific notation

This is a website designed for both teachers and students that addresses scientific notation from the Australian Curriculum for year 9 students. It contains material on scientific notation using index laws and multiplication, division and indices. There are pages for both teachers and students. The student pages contain ...

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Very large and very small numbers

This is a website designed for both teachers and students, which addresses very large and very small numbers from the Australian Curriculum for year 9 students. It contains material on the vocabulary and notation for dealing with very large and very small numbers using scientific notation. There are pages for both teachers ...

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Similarity

This is a website designed for both teachers and students, which addresses similarity from the Australian Curriculum for year 9 students. It contains material on enlargement transformation and similar triangles. There are pages for both teachers and students. The student pages contain interactive questions for students ...

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Trigonometry

This is a website designed for both teachers and students, which addresses content on trigonometry from the Australian Curriculum for year 9 students. It contains material on working with the similarity of right-angled triangles, the three basic trigonometric ratios, and solving problems with trigonometry. There are pages ...

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Surface area and volume of prisms and cylinders

This is a website designed for both teachers and students, which addresses the surface area and volume of prisms and cylinders from the Australian Curriculum for year 9 students. It contains material on calculating the surface area and volume of prisms and cylinders. There are pages for both teachers and students. The student ...

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Coordinate geometry

This is a website designed for both teachers and students that addresses coordinate geometry from the Australian Curriculum for year 9 students. It contains material that shows the connection between algebra and geometry through graphs of lines and curves. There are pages for both teachers and students. The student pages ...

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Transformation: Year 9 – planning tool

This planning resource for Year 9 is for the topic of Transformation. Students explore and develop their understanding of the enlargement transformation using dynamic geometry software. They will investigate what changes and what remains the same when a shape or object is enlarged. Students will look for patterns in the ...

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Mathematical modelling (Algebra): Year 9 – planning tool

This planning resource for Year 9 is for the topic of Mathematical modelling. Students use algebraic rules, tables, graphs and digital tools to construct linear and quadratic models for a range of real-life situations, make predictions and solve related problems. They spend time identifying variables to formulate the models ...

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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.

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Operations: Foundation to Year 9

This comprehensive resource describes the progression of ideas that cover addition and subtraction of integers; multiplication and division of integers; the four operations with common and decimal fractions; and operation applications with percent, rate and ratio.

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Geometry: Foundation to Year 9

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