In this section we will discuss about introduction to triangles.
A plane figure formed three non-parallel line segments is called a triangle.
Non-collinear points join to form a Triangle.
Parts of Triangles :
Vertices : A, B, C
Sides : AB, BC , CA
Angles : ∠BAC, ∠ABC, ∠ACB.
Opposite Sides : side opposite to
∠BAC ----> BC
∠ABC ----> AC
∠ACB ----> AB
Interior and Exterior Of Triangle
In triangle ABC, there are three parts :
Interior region : The points lie inside the region enclosed by triangle. On the sides : The points lie on the sides of the triangle. Exterior region : The points lie outside the region enclosed by triangle.
Interior points : P and S
Exterior points : Q
On the sides : R and T
The interior of Δ ABC together with the ΔABC itself, is called the triangular region ABC.