Răspunsuri

2014-06-02T19:39:01+03:00
P_{romb}=4l=36cm \\ l=36:4 \\ l=9cm \\ AB=BC-CD=AD=9cm \\  
<ABD=<ABC / 2 = 60*
<ADB=<ABC / 2 = 60*
Deci ΔABD este echilateral, AB=AD=BD=9cm