Author: BENNY VARGHESE
Date: 19/10/2006

A BENTECH PRESENTATION ......

EXTERIOR ANGLE  PROPERTY OF TRIANGLE

Don't u see that Red+Blue+Green makes 
Semi circular disc and hence A+B+C=180 ?

Drag points A,B,C to get various cases of the thm

A presentation from 

Benny Varghese 
PGT Maths 
JNV Pathanamthitta

A = (7.97552235921224, 2.258049011230466)
B = (2.3723958333333335, -7.783203125)
C = (13.035696919759117, -5.408882141113282)
a = Ray(B, C)
b = Segment(B, A)
c = Segment(C, A)
D = Point(b)
E = Point(a)
F = Point(b)
G = Point(c)
H = Point(c)
I = Point(b)
δ = Angle(F, A, G)
ε = Angle(E, B, D)
d = Line(C, b)
J = Point(a)
K = Point(d)
L = Point(d)
M = Point(c)
text1: "exterior angle  C  = " + δ + " +  " + ε + " =A + B"
N = Point(a)
u = Vector(B, N)
O = Point(d)
v = Vector(C, O)
α = Angle(C, B, A)
B' = Mirror(B, C)
γ = Angle(B, A, C)
A' = Rotate(A, -γ, C)
ζ = Angle(A', C, A)
B''_1 = Rotate(B', α, C)
β = Angle(B', C, B''_1)
η = Angle(A, C, B)