Respuesta :

3

1) Let's sketch that, to better understand this:

2) Considering the Segment Addition Postulate, we can write that:

DF = DE + EF Plug into that the given values

9 = 6 + EF

9-6 = 6-6 + EF

3 = EF

EF =3

3) Hence, the line segment EF is 3 units long

Ver imagen CoriannaG176182