I need help finding the missing angle with work plz
ANSWER ASAP!!!!!!

Answer:
The unknown angle is 80
Step-by-step explanation:
The sum of the angles of a triangle add to 180 degrees
Let the unknown angle be x
20+80+x = 180
Add like terms
100+x = 180
Subtract 100 from each side
100-100+x=180-100
x = 80