9514 1404 393
Answer:
- a = 30
- b = 15
- c = 3
- d = 30
- e = 10
- f = 20
Explanation:
The acute angles are all 60°, and the obtuse angles are all the supplement of that, 120°.
Working from the left, we have ...
a +30 = 60 ⇒ a = 30
30 +2b = 60 ⇒ b = 15
5b -5c = 60 ⇒ 15 -c = 12 ⇒ c = 3
10c +d = 60 ⇒ d = 30
2d +6e = 120 ⇒ 60 +6e = 120 ⇒ e = 10
4f +4e = 120 ⇒ f +10 = 30 ⇒ f = 20