Gegeben  \ sind:  \
\beta = 60^0, \ \omega_\beta =4cm, \ a=7cm

$\varphi = \frac{\beta}{2}$

Lösung \ ist: \ \Delta ABC

C = (3.0780559317531844, 3.3092441345064074)
B = Point(Circle[C, 7])
a = Segment(C, B)
C' = Rotate(C, 30°, B)
φ = Angle(C, B, C')
b = Line(B, C')
c = Circle(B, 4)
P = Intersect(c, b, 2)
d = Line(C, P)
C'_1 = Rotate(C, 60°, B)
β = Angle(C, B, C'_1)
e = Line(B, C'_1)
A = Intersect(d, e)
Vieleck1, c_1, a_1, b_1 = Polygon(A, B, C)