# Mathematics / Year 9 / Measurement and Geometry / Geometric reasoning

Curriculum content descriptions

Use the enlargement transformation to explain similarity and develop the conditions for triangles to be similar (ACMMG220)

Elaborations
• establishing the conditions for similarity of two triangles and comparing this to the conditions for congruence
• using the properties of similarity and ratio, and correct mathematical notation and language, to solve problems involving enlargement (for example, scale diagrams)
• using the enlargement transformation to establish similarity, understanding that similarity and congruence help describe relationships between geometrical shapes and are important elements of reasoning and proof
General capabilities
• Literacy Literacy
• Numeracy Numeracy
ScOT terms

Dilation,  Triangles (Shapes),  Similarity (Geometry)

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