Joey Wong's answer to Adwin's Secondary 1 Maths Singapore question.

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Joey Wong
Joey Wong's answer
8 answers (A Helpful Person)
Not sure though
Adwin
Adwin
4 years ago
Hi, thanks for answering but the answer is incorrect. It should be 150°.

I drew the triangle, similar in ratio geometrically, then cut it out and measured the angle with a protractor and verified it to be 150°.

As for why it is so... I don't know.