>>13740278You're forgetting you can calculate c directly as the area of the segment of a circle.
a + b + c + d + e = 8
a + b = c + d + e
therefore
c + d + e = 4
a + b + c + d + e = 8
b + c = 2*pi
a + d + e = 8 - 2*pi
a + d = e
therefore
e = 4 - pi
c + d + e = 4
e = 4 - pi
c + d = pi
therefore
d = pi - c
now to calculate c
let Θ be the upper right angle. Then the central angle of the sector that forms C is α=pi-2*Θ (see pic)
For Θ, we know that tan(Θ) = 2/4 = 0.5, so Θ = arctan(0.5) and α=pi-2*arctan(0.5) = 2.2142
The area of C is then given by
c = (r^2 / 2) * (α - sin(α))
The radius of the circle is 2.
c = (4/2) * (2.2142 - sin(2.2142) = 2.8285948711
d = pi - c
d = 0.31299
