Answer:
x=51
Step-by-step explanation:
The external angle is equal to the sum of the opposite interior angles
3x-22 = x+80
Subtract x from each side
3x-22-x = x+80-x
2x-22 = 80
Add 22 to each side
2x-22+22 = 80+22
2x = 102
Divide by 2
2x/2 = 102/2
x = 51
