Answer:
u = 59
Step-by-step explanation:
The sum of the exterior angle is equal to the sum of the opposite interior angles
u+ u-19 = u+40
2u -19 = u+40
Subtract u from each side
2u-19-u = u+40-u
u-19 = 40
Add 19 to each side
u+19-19 =40+19
