Arnold K H Tan's answer to shoo0p's Secondary 3 E Maths Singapore question.

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Arnold K H Tan
Arnold K H Tan's answer
2155 answers (A Helpful Person)
1st
Bii) there are 2 different approaches. I used the simpler one: comparing a common triangle. Comparing triangle QOR and QRP is easiest using area of triangle = ½ x ab x sin(theta)