In Geometry, a **triangle is the most crucial shape**, characterized as a closed two-dimensional diagram containing 3 sides, 3 angles, and 3 vertices. In simple words, a triangle is a polygon with 3 sides. Words triangle is taken native the Latin native ‘triangulus,’ which way three-cornered.

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During ancient times, astronomers had created a an approach called triangulation to recognize the distances of the distant stars. They measure up the distance from two various locations, then measure up the angle produced by change or parallax, developed by the observer’s movement in between the 2 locations. Then they used to use the legislation of sines for calculating the compelled distance.

The Egyptians created the pyramids approximately 2900 B.C. Its shape is in reality that that a 3D pyramid, which has actually triangular faces. The is a perfectly engineered version that that is lengths and angles on every sides space the same. Miletus (624 BC – 547 BC), a Greek mathematician, adopted Egypt’s geometry and was brought to Greece.

Aristarchus (310 BC – 250 BC), a Greek mathematician, provided the above method to discover the distance between the Earth and the Moon. Eratosthenes (276 BC – 195 BC), again, offered the same method to identify the distance about the surface of earth (called circumference).

This post will** discuss the definition of a triangle**, the **different types of triangles** and their properties, and their real-life applications.

## What is a Triangle?

A triangle is a two-dimensional closed number with 3 sides. It is a polygon with three corners, three vertices, and three angles joined together that forms a closeup of the door diagram. We usage the symbol ∆ to denote a triangle.

Figures A and B are triangles.

Solution

This is one isosceles triangle. 2 sides room equal, and also two angles are equal in measurement.

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### Applications of Triangles

*Let’s explore some of the real-life applications that triangles:*