Répondre :
c'est une configuration de Thalès
1) OE/OD = OC/OD => OE = OD.OC/OD = 6.10,8/7,2 = 9cm
BD/CE = 6/9 =2/3 => BD = 5,1.2/3 = 3,4cm
2)on a que 2/6 = 2,4/7,2 = 1/3 => FG//BD réciproque de Thalès
1) OE/OD = OC/OD => OE = OD.OC/OD = 6.10,8/7,2 = 9cm
BD/CE = 6/9 =2/3 => BD = 5,1.2/3 = 3,4cm
2)on a que 2/6 = 2,4/7,2 = 1/3 => FG//BD réciproque de Thalès