Perhatikan gambar berikut. Jika panjang Ad=36 cm, panjang DC=...

36 cm juga,,karna panjang AD sama dgn panjang DC

AB = AD . sin60
AB = 36 . 1/2 √3
AB = 18 √3

BD = AD. cos60
BD = 36 . 1/2
BD = 18

AB/BC = Tan30
AB/(BD + DC) = Tan30
18√3 / (18 + DC) = 1/3 √3
3 . 18√3 = √3 (18 + DC)
3 . 18 = 18 + DC
DC = 54 - 18
DC = 36