Answer:
x = 80
Step-by-step explanation:
We know AEC + CEB = 180 since it forms a line
AEC + 160 = 180
AEC = 20
We also know that
AEC + AEF + FED = 180 since it forms a line
20 + x+ 80 = 180
Combine like terms
100 +x = 180
Subtract 100 from each side
100+x-100= 180-100
x = 80
