Respuesta :

The sum of the angles shown is ...
  720° = 3x + 240°
Then
  480° = 3x
  160° = x

Angle F = 160° -20° = 140°

Answer:

f =140

Step-by-step explanation:

took the test

 720° = 3x + 240°

Then

 480° = 3x

 160° = x

Angle F = 160° -20° = 140°