Perimeter of triangle
Remember that, Sum of all the angles is always
Basically there are three types of triangles excluding right angle triangle. Let me tell you how they vary from each other.
Scalene Triangle: No side of triangle is equal.
Isosceles Triangle: Two sides of triangle are equal.
Equilateral Triangle: All sides of triangle are equal.
|Definition||a ne b ne c||ane b = c||a = b = c|
Properties of external angles of Triangle:
1. Sum of all exterior angles is
Study the following set of triangles and their exterior angles,
a, b, c to Interior angles. p, q, r and s, t, u to Exterior angles.
So, sum of exterior angles
2. Next property of exterior angle which is important in paper point of view:
External angle = Sum of two internal angles.
For example: In above figures,
Following triangle is a right angle triangle i.e. a triangle with one out of three
Example: In following figure, CE is perpendicular to AB, angle
Solution: To Find: angle BDA
For this what we need --- angle BAD Because, Sum of all angles
Consider, triangle ECA,
Now, come to triangle ABD,
Example: In given figure. BC is produced to D and angle
Solution: In above figure, ACD is an exterior angle, and according to property, Exterior angle = Sum of interior angles Therefore,
This is not the end of this chapter. These are just the basics. In next session, I will discuss some important results, properties (congruency, similarity) and much more. Always remember, Geometry needs practice and time.