Eric Nicholas K's answer to Nabanita bose's Secondary 4 E Maths Singapore question.

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Eric Nicholas K
Eric Nicholas K's answer
3962 answers (Tutor Details)
Knowledge needed are

1. Formulae for interior/exterior angles of regular polygon

2. Concepts of triangles, alternate angles etc.

3. Recognising some form of symmetry in the diagram

4. Reasoning (especially for part b)