a)Daca,tr.este,dr,isoscel=>m(ABC)=m(ACB)=(180-90)/2=90/2=45
b)De,asemenea,tr.ADB,este,dr,isoscel=>AD=BC/2=3
c)De,asemenea,tr.ADC,este,dr,isoscel=>bisectoarea,DE,imparte,unghiul,ADC,in,doua,unghiuri,de,45.Unghiul,C,este,de,45=>m(DEC)=90=>DEparalel,cu,AB.
Fiind,tr,dr,isoscel,DE=EA.