# The Triangle And Its Properties

Triangle is a basic shape in geometry which can be defined as a closed figure bounded by 3 line segments or edges, it is a 3 sided polygon.
Before understanding the concept of properties of triangles we will understand about its types:
Types of triangles:
Triangles are categorized on the basis of the side length and the angles of the triangle.
Types of triangles with relative to length of the sides are:
1. Scalene triangle: The triangle in which all sides are of unequal length and angles are also different.
2. Isosceles triangle: This type of triangle has two sides of equal length and has two same angles.
3. Equilateral triangle: Where all three sides of the triangle are of same length and all angles are also equal with all three angles of 60 degree.
Types of triangle in relation to internal angles:
1. Right angle triangle: It is a type of triangle in which one interior angle is of 90 degrees. The side of the triangle which is opposite to the 90 degree angle is the longest side and called as hypotenuse and the other two are called as legs. Pythagorean Theorem is applicable on right angle triangle.
2. Oblique triangles are those triangles which do not have any angle equal to 90 degree.
3. Acute triangle are those triangles whose angles are lesser than 90 degree.
4. Obtuse triangle are those triangles whose one angle measures greater than 90 degree.
Some properties of a Triangle are shown below:
1. Vertex: It is the point where two sides of a triangle intersect each other.
2. Base: Base of the triangle can be one of the three sides normally considered the one which is at bottom and is used for calculating the area of the triangle. In isosceles triangle the side which is unequal to others is considered as base.
3. Altitude: This is the line which is perpendicular from the base to the opposite vertex in the triangle. If we have three bases then altitudes will also be three in triangle. Intersection point of altitudes is called as orthocenter of a triangle.
4. Median: It is a line drawn from the vertex to the opposite side dividing it into two equal parts. Intersection of median is called as ‘Centroid’ of the triangle. Medians can be extended outside the triangle too.
5. Area of triangle is ½* base * height.
6. Perimeter of triangle: The distance around the triangle sides or we can say sum of all the sides.
7. Interior Angles: The angles which are inside the triangle on each vertex are called as interior angles.
8. Exterior Angles: The angles outside the triangle when sides are extended are exterior angles.
These is all about triangle properties.

Math Topics