Question

URGENT DAU COROANA!!​

Answer 1

figura ABCD = dreptunghi

AC ∩ BD = {O}

AC; BD = diagonale => OA = OC = BO = OD

a) ∡AOB = 100°}  =>  ΔAOB = isoscel => ∡ABO = ∡BAO = $\frac{180-100}{2}$ = 40°

   AO = BO       }        

b) ∡AOD = 70° }   =>   ΔAOD = isoscel => ∡DAO = ∡ADO = $\frac{180-70}{2}$ = 55°

   AO = DO      }