How old is the (Pythagorean) theorem?
This is an introductory lesson in a series of lessons on Pythagoras theorem. Students learn about Pythagoras’ theorem and its application in calculating lengths in rightangled triangles. They explore the statement of the theorem, some of its history, a simple geometric proof and visual demonstrations of the theorem. Students apply the theorem to the two types of problem calculating the length of the third side of a rightangled triangle, given the lengths of the other two sides.
Additional details 

Year level(s)  Year 8 

Audience  Teacher 
Purpose  Teaching resource 
Format  Web page 
Teaching strategies and pedagogical approaches  Mathematics investigation, Questioning, Explicit teaching, Concrete Representational Abstract model, Worked examples 
Keywords  problem solving, rightangled triangles, triangles, Maths Hub lesson plan 
Curriculum alignment 

Curriculum connections  Critical and creative thinking 
Strand and focus  Number, Measurement 
Topics  Pythagoras and trigonometry 
AC: Mathematics (V9.0) content descriptions 
AC9M8N01
Recognise irrational numbers in applied contexts, including square roots and Π
AC9M8M06
Use Pythagoras' theorem to solve problems involving the side lengths of rightangled triangles 
Numeracy progression 
Understanding geometric properties (P7)
Understanding units of measurement (P10) Multiplicative strategies (P9) 
Copyright details 

Organisation  Commonwealth of Australia 
Copyright  © 2024 Commonwealth of Australia. Creative Commons BY 4.0. 
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