Answer:
b = 68°
Explanation:
he's your solution
=> angle of a polygon is given by =
(2n -4)*90°
=>(2*8 - 4) *90°
=> 12*90°
=> sum of all angles = 1080°
=> now, 150°+144°+127°+2b+b+50°+2b+11°+2b-20°+2b+6° = 1080°
=> 9b + 468° = 1080°
=> 9b = 612°
=> b= 612°/9
=> 68°
hope it helps