Answer:
30°
Step-by-step explanation:
∠A + ∠B + ∠C = 180
∠B = ∠A + 20
∠C = 2 * ∠B
<A + (∠A + 20) + (2 * ∠B) = 180
<A + (∠A + 20) + (2 * (∠A + 20)) = 180
<A + (∠A + 20) + 2∠A + 40 = 180
4∠A + 60 = 180
4∠A = 120
∠A = 30
Answer:
A=πr2=π·212≈1385.44236cm²
If you would like to simplify this equation, the only thing that you can do is simplify the radical.
=
Since 3 appears twice, we can factor it out of the radical. This gives us our answer of: