Answer:
156
The angle measurement is reasonable. It must be less than 180 which is a straight line
Step-by-step explanation:
Vertical angles are equal
3x = x+104
Subtract x from each side
3x-x = x+104-x
2x = 104
Divide by 2
2x/2 = 104/2
x = 52
3x = 3*52 = 156
The angle measurement is reasonable. It must be less than 180 which is a straight line