Kolmnurga sisenurkade summa
Author: Tiiu  Sasi
Date: 17. Märts 2009. a

Liiguta nurkade liugureid δ ja ε 180° -ni  ja veendu, et kolmnurga 
nurkade summa on  alati 180°.

KOLMNURGA SISENURKADE SUMMA ON 180°

A = (3.17332, -2.60232)
B = (7.420420000000003, 2.404659999999999)
C = (14.37792, 0.2532799999999997)
poly1, c, a, b = Polygon(A, B, C)
α, β, γ = Angle(poly1)
D = Midpoint(b)
E = Midpoint(c)
δ = 3.141592653589793 rad (slider from 0 to 3.141592653589793, step 0.17453292519943295)
ε = 3.141592653589793 rad (slider from 0 to 3.141592653589793, step 0.17453292519943295)
A' = Rotate(A, -δ, D)
B' = Rotate(B, -δ, D)
C' = Rotate(C, -δ, D)
poly1', c', a', b' = Polygon(A', B', C')
A'_1 = Rotate(A, ε, E)
B'_1 = Rotate(B, ε, E)
C'_1 = Rotate(C, ε, E)
poly1'_1, c'_1, a'_1, b'_1 = Polygon(A'_1, B'_1, C'_1)
ζ, η, θ = Angle(poly1'_1)
ι, κ, λ = Angle(poly1')
text2: "α + β + γ=" + α + "+" + β + "+" + γ + "=180°"