What is the length of DF?
F
За
IT
E
G
a +6
D
DF =

Answer:
18
Step-by-step explanation:
Triangles FEG and DEG are congruent by SAS, so DG = FG.
a+6 = 3a
6 = 2a
3 = a
3a = 3·3 = 9 = FG = DG
DF = 9+9 = 18