Answer:
23
Step-by-step explanation:
Sum of all angles is 180
So b + 36 + 4b - 16 + (180 - (8b - 49)) = 180
Notice that 3rd angle is 180 - (8b - 49)
b + 36 + 4b - 16 + 180 - 8b + 49 = 180
3b = 69
b = 23
