∴AB=CD,AB∥CD
∴∠EDF=∠EBA,∠EFD=∠EAB
∴⊿EDF∽EBA
∴FD/AB=EF/AE= 1/2
∴FD=? AB=? laser record
∴CF=? CD=? ab blood type
Similarly, it is easy to prove ⊿FCG∽⊿ABG.
∴FG/AG=FC/AB= 1/2
∴FG=? Adjutant general
∴FG=AF
And AF=2EF.
∴FG=2EF