1. Introduction to Triangles

A plane figure bound by three
 non concurrent line segments
 in plane is called a triangle

3 Vertices A, B, C
3 Angles ∠A, ∠B, ∠C
3 Sides AB, BC, CA ( Interior angles)

Author - Preetha Rocky Fernandis
Copyright - Creative Commons AttributionShare Alike
(CC By SA)

A_1 = (2, -6.490485667928609)
B_1 = (27.04, -6.39048566792861)
f = Line(A_1, B_1)
C_1 = (0.8834072471606293, -8.86183017847485)
D = (13.683407247160629, 4.558169821525153)
g = Line(C_1, D)
E = (10.260387236343963, 1.5627560843699309)
F = (20.06038723634396, -10.29724391563007)
h = Line(E, F)
A = Intersect(h, g)
B = Intersect(f, g)
C = Intersect(h, f)
t1, a, c, b = Polygon(A, B, C)
α = Angle(B, A, C)
β = Angle(C, B, A)
γ = Angle(A, C, B)
Textt1: "Area of  " + (Name[A]) + (Name[B]) + (Name[C]) + " = " + t1
Pointt1_1 = PointIn(t1)
Pointt1_2 = PointIn(t1)
d = Perimeter(t1)
Pointt1_3 = PointIn(t1)
e = Perimeter(t1)
Pointt1_4 = PointIn(t1)
i = Perimeter(t1)
text4: "Perimeter of  " + (Name[A]) + (Name[B]) + (Name[C]) + " = " + i
Pointt1 = PointIn(t1)
perimeterofthetriangle: a + b + c
j: ((a * b) * c)
text5: "" + text4 + ""
sumoftheanglesofthetriangle: α + β + γ
G = Point(f)
H = Point(g)
I = Point(h)
J = Point(g)