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Area of a triangle
The prompt will challenge students to think about the area of a non-right-angled triangle, using the general sine formula. They also explore the concept of proof, deepening their conceptual understanding. The resource includes classroom examples, teacher notes and guided questions.
|Year level(s)||Year 9, Year 10|
|Purpose||Assessment task, Extension, Student task, Teaching resource|
|Teaching strategies and pedagogical approaches||Collaborative learning, Differentiated teaching, Explicit teaching, Feedback, Mathematics investigation|
|Keywords||sine, triangle, angle, proof, area|
|Curriculum connections||Critical and creative thinking, Numeracy|
|Strand and focus||Space, Measurement, Algebra, Apply understanding, Build understanding|
|Topics||Algebraic expressions, Angles and geometric reasoning|
|AC: Mathematics (V9.0) content descriptions||
Recognise the constancy of the sine, cosine and tangent ratios for a given angle in right-angled triangles using properties of similarity
Solve practical problems applying Pythagoras' theorem and trigonometry of right-angled triangles, including problems involving direction and angles of elevation and depression
Proportional thinking (P7)
Understanding geometric properties (P7)
Understanding units of measurement (P10)
© Andrew Blair 2012-21. Creative Commons BY-NC-SA 4.0.