[AB] est le côté adjacent à l'angle ABC.

On peut donc écrire cos(ABC) = AB/BC

[AC] est le côté adjacent à l'angle ACB.

On peut donc écrire cos(ACB) = AC/BC

En appliquant la somme des angles, on trouve

AB = 12 (slider from 0 to 15, step 0.1)
ABC = 0.6981317007977318 rad (slider from 0 to 1.5707963267948966, step 0.017453292519943295)
A = (2.3, -0.7666666666666666)
c = Circle(A, AB)
B = Point(c)
b = Segment(A, B)
d = OrthogonalLine(A, b)
C_1 = Rotate(A, -ABC, B)
e = Ray(B, C_1)
C = Intersect(d, e)
g = Distance(A, C)
δ = Angle(A, C, B)
f = Distance(B, C)
β = Angle(A, B, C_1)
P, b_1, c_1, a_1 = Polygon(C, A, B)
γ = Angle(C, B, A)
T2: "ACB = 90° - " + ABC + " = " + δ
T5: "cos(" + ABC + ") = " + AB + " / BC donc BC = " + AB + " / cos(" + ABC + ")" + " = " + f
T8: "cos(" + δ + ") = AC / " + f + " donc AC = " + f + " x cos(" + ABC + ")" + " = " + g