Please note: This site contains links to websites not controlled by the Australian Government or ESA. More information here.
reSolve: Mechanical Linkages: Similar Triangles
This sequence of lessons explores the geometry of similar triangles using two real-world objects: ironing boards and pantographs. In the first lesson, students investigate different ironing board leg lengths and pivot positions using similar and congruent triangles. In the second lesson, they use their knowledge of parallelogram properties and similar triangles to explore and explain how pantographs work. Each lesson is outlined in detail including curriculum links, materials needed, sample answers, discussion points and student resources such as links for simulations online. This sequence is part of the reSolve: Maths by Inquiry special topic 'Mechanical linkages and deductive geometry'.
|Year level(s)||Year 9|
|Teaching strategies and pedagogical approaches||Mathematics investigation|
|Keywords||triangles (shapes), dilation, similarity (geometry), explicit teaching|
|Strand and focus||Space, Build understanding, Apply understanding|
|Topics||Angles and geometric reasoning|
|AC: Mathematics (V9.0) content descriptions||
Solve spatial problems, applying angle properties, scale, similarity, Pythagoras' theorem and trigonometry in right-angled triangles
Understanding geometric properties (P7)
Understanding units of measurement (P10)
Proportional thinking (P7)
reSolve Maths by Inquiry
© Australian Government Department of Education, Skills and Employment 2021. Creative Commons BY-NC-SA 4.0.