Respuesta :
as the exterior angle is known
sum of that angle and f angle = 180
142 + f = 180
f = 180 - 142
f = 38
Answer:
38
Step-by-step explanation:
- Add the angle and f angle (180)
- Now add 142 + f = 180
- Now subtract 180 - 142 (= f)
- Finally you get your answer 38
Hope this helps you :)