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'.