Question

[Vũ Gia Bình]

Bai 1: Chung minh 2 tam giac ABC ya DEF dong dang va viet cas cap goc bang
nhau, neu biet mot trong cac truong hop sau:
a) AB =4cm, BC = 6cm, AC =5cm, DE = 10cm, DF = 12cm, EF =8cm.

b) AB = 24cm, BC =21cm, AC =27cm, DE = 28cm, DF = 36cm, EF = 32cm.
c) AB =DE =12cm, AC =DF = 18cm, BC=27cm, EF =8cm.