Pythagoras’ theorem two ways
In this lesson, students use Pythagoras’ theorem to calculate unknown side lengths in rightangled triangles after undertaking a stepbystep method of working through visual and algebraic proofs simultaneously. This will help students develop deeper connections between algebra and measurement in this context.
Additional details 

Year level(s)  Year 9 

Audience  Teacher 
Purpose  Teaching resource 
Format  Web page 
Teaching strategies and pedagogical approaches  Classroom talks, Mathematics investigation, Worked examples, Explicit teaching 
Keywords  rightangled triangles, problem solving, proofs, congruency, similarity, algorithms, Maths Hub lesson plan 
Curriculum alignment 

Curriculum connections  Critical and creative thinking 
Strand and focus  Measurement 
Topics  Pythagoras and trigonometry, Using units of measurement, Computational thinking 
AC: Mathematics (V9.0) content descriptions 
AC9M9M03
Solve spatial problems, applying angle properties, scale, similarity, Pythagoras' theorem and trigonometry in rightangled triangles 
Numeracy progression 
Understanding geometric properties (P7)
Understanding units of measurement (P10) Proportional thinking (P7) 
Copyright details 

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