The most important shape in geometry is the triangle, which is described as a closed two-dimensional figure with three angles, three sides, and three vertices. In other words, a triangle is a three-sided polygon. The word triangle comes from the Latin word “triangulus,” which means “three corners.” Let’s take a closer look at the many forms of triangles.

Astronomers used a method called triangulation to calculate the distances between distant stars in the past. They measure the distance between two points, then calculate the angle caused by the shift in perspective or parallax caused by the observer’s movement between the two points. They then used sine regulation to determine the required range.

Around 2900 BC, Egyptian pyramids were built. Its shape is that of a three-dimensional pyramid with Triangle faces. It’s a completely engineered version with the same lengths and angles on all sides. Miletus, a Greek mathematician, borrowed Egypt’s geometry and created Greece.


The above approach was used by Aristarchus (310 BC–250 BC), a Greek mathematician, to calculate the distance between the planet and the Moon. Eratosthenes (276 BC–195 BC) used the same method to calculate the distance around the Earth’s surface (called area).


In this post, we’ll look at the definition of Triangle, many types of Triangle and residential or commercial buildings, and Triangle’s real-world applications.


What exactly is a triangle?


A triangle is a three-sided closed two-dimensional number. It’s a closed representation of a polygon with three edges, three vertices, and three angles. The symbol is used to depict a triangle.


Triangles come in a variety of shapes and sizes.


Triangles are classified into many types based on:


Their lengths on each side


Angles from within


Triangles are classified based on the inside angle gauge.


Triangles can be classified into three categories based on the step of interior angles:





Triangle with a sharp point


An acute inclination Triangles with all three indoor angles less than 90 degrees are known as triangles.


Each of the angles, a, b, and c, is less than 90 degrees.


Triangle with an acute angle


An obtuse triangle is one in which the interior angles are greater than 90 degrees.


Angle an is far more obtuse than angles b and c, which are both acute.


Triangle with a right angle


A right triangle is one in which the angles are all exactly 90 degrees. The hypotenuse is the longest and widest side of a proper triangle.


Triangles are classified based on the length of their sides.


Based on the lengths of their sides, triangles can be divided into three types:





Triangle of isosceles


Isosceles is a type of isosceles. A triangle is a shape with two sides and two angles that are equal. Making an arc on each side of a triangle reveals the triangle’s equal lengths.


Triangle with equal sides


All three sides of an equilateral triangle are equal, as are all three interior angles. Each indoor angle of an equilateral triangle is 60 levels in this scenario. Because all three angles are equal, an equilateral triangle is also known as an equiangular triangle.


The sides of an equilateral triangle are AB = BC = AC and ABC = ACB = BAC.


Remember that the angles of an equilateral triangle are independent of the size of the sides.


Triangle of Scalene


All of the sides of a scalene triangle have different steps, and all of the interior angles are also varied.


Triangle Characteristics


Triangle’s qualities are widely used. It was utilized by many mathematicians to solve their issues. Buildings of triangles are used extensively in Euclidean geometry and trigonometry.


Here are a few examples of typical triangle residential or commercial properties:







Worked examples of many triangle types.


1st example


In the Triangle below, find the value of angle x.




This is an isosceles triangle, which has two sides and two angles that are both equal. Therefore,


x = (180°–70°)/2


x=110 degrees/ 2


= 55 degrees.


Example No. 2


In the ideal Triangle shown below, find angle y.




An perfect triangle has one angle of 90 degrees.


As a result, we have: y + 50 + 90 = 180.


y = (180–140) °, and


y = 40 degrees