Lau Guan Yih's answer to Yx._-tan's Secondary 3 E Maths Singapore question.

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Lau Guan Yih
Lau Guan Yih's answer
59 answers (Tutor Details)
1st
You had the right idea calculating AP.
However, you used the wrong numbers.
Because both triangles are in different orientation, it helps to withdraw Triangle ABC to be the same orientation as big Triangle AQP. From here, things should be pretty straight forward.