Tan Zihao's answer to Justus Tan's Secondary 2 Maths question.

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Tan Zihao
Tan Zihao's answer
13 answers (Tutor Details)
1st
7) Key word is equilateral triangle (all sides equal)
Triangle has 3 sides and hence perimeter is 3x length = 21cm.

Therefore length is 21/3=7cm