**INTRODUCTION**

A triangle is a polygon with three edges and three vertices. It is one of the basic shapes in geometry. A triangle with vertices A, B, and C is denoted withÂ Â Â Â Â Â ABC. Triangles are assumed to be two-dimensional plane figures, unless the context provides otherwise.

**MEANING OF TRIANGLE**

A triangle is a three-sided polygon, which has three vertices. It is a plane figure bounded by three straight lines. The length of the sides can vary but the length of the largest sides canâ€™t be equal to or greater than the sum of the other two sides. The formula for calculating the area of triangle is: Â½ base x height. The figure below shows the typical shape of a triangle. The sum total of all the interior angles in a triangle is 180o.Â Triangles are described by

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