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geometrya polygon with three edges and three vertices.
A triangle is a three-sided polygon with three edges and three vertices. It is one of the simplest and most fundamental shapes in geometry.
Triangles can be classified by their sides and angles. An equilateral triangle has all sides of equal length, an isosceles triangle has two sides of equal length, and a scalene triangle has all sides of different lengths. A right triangle has one angle of exactly 90 degrees, an acute triangle has all angles less than 90 degrees, and an obtuse triangle has one angle greater than 90 degrees.
A vertex is a point where two or more lines or edges meet.
An angle is the figure formed by two rays sharing a common endpoint called the vertex. Its size, measured in degrees or radians, is the amount of rotation needed to align one ray with the other.
A right triangle (or right-angled triangle) is a triangle in which one of the angles is a right angle (90 degrees). The side opposite the right angle is called the hypotenuse, and it is the longest side. The other two sides are known as the adjacent and opposite sides, relative to the non-right angle being referenced.