Answer:
b = 110 degrees
Explanation:
We can solve the problem as stated, but those numbers are nowhere near the angles of that (or any) pentagon. The angles of a pentagon add up to 540°, not 360° as stated.
And just look at the angles: each of them is clearly >90°, yet they've written silly numbers in.
So forget the drawing, but we can solve this question:
These 5 things add up to 360. What's b?
Lay it out:
30 + 40 + 20 + 50 + 2b = 360
Group like terms:
(30 + 40 +20 +50) + 2b = 360
Add:
140 + 2b = 360
Subtract 140 from both sides:
2b = 220
Divide by 2:
b = 110 degrees
Always check your work:
Does 30 + 40 + 20 + 50 + 2(110) equal 360? Yes, so our answer must be correct.