AC Lim's answer to Darren's Secondary 1 Maths Singapore question.

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AC Lim
Ac Lim's answer
3142 answers (A Helpful Person)
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Hope this help
Darren
Darren
5 months ago
How u get 5?
AC Lim
AC Lim
5 months ago
If you observe triangle ABD = Triangle BCD
and are equilateral triangle, Each have 60 deg. Therefore, height of BCD meet at center of DC. DC/2=5cm.

Another way to get height = 10 cos 30
or
10 Sin 60 (Since each angle are 60)