Jawabanmu

Jawaban paling cerdas!
2014-02-21T13:01:30+07:00
Dik : AC = 12cm
       AB= 6 cm
       CB = 8 cm
       garis AB di perpanjang ke titik D, jadi
misal : BD = x
 AD = AB+BD = (6 + x) cm
maka:
AB/ AD = 3 / 8
6cm / (6 + x)cm = 3/8
(6)(8)=3 (6+x)
48 = 18 + 3x
3x = 30
x = 10

jadi AD = 10+6=16cm
sehingga,
CD= \sqrt{ AD^{2}+ AC^{2} }
= \sqrt{ 16^{2} + 12^{2} } = \sqrt{400} = 20cm
     
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