Triangle Calculator

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2 Known Sides

Triangle Calculator

Please enter three values, including at least one side, into the following six fields and click the "Calculate" button. When radians are used as the angle unit, they can have values like pi/2, pi/4, and so on.

A triangle is a polygon with three vertices. A vertex is a location where two or more curves, lines, or edges intersect; in the example of a triangle, the three vertices are connected by three line segments known as edges. A triangle is commonly identified by its vertices. A triangle having vertices a, b, and c is frequently abbreviated as Δabc. Furthermore, triangles are typically characterized using the lengths of their sides and internal angles. For example, an equilateral triangle is one with equal lengths on all three sides, but an isosceles triangle has equal lengths on two sides. Scalene is used to describe a triangle in which none of the sides are equal in size.

Tick marks on the edge of a triangle are a popular notation for the length of the side, with the same amount of ticks representing equal length. Similar notation exists for a triangle's internal angles, which are represented by varying numbers of concentric arcs positioned at its vertices. As shown in the triangles above, a triangle's length and internal angles are closely related, so an equilateral triangle has three equal internal angles and three equal-length sides. The triangle presented in the calculator is not shown to scale; at the same time, it appears equilateral (and contains angle markings that would normally be read as equal); it is not necessarily equilateral and is only a representation of a triangle. When actual values are supplied, the calculator's output will match the geometry of the input triangle.

Triangles are classed according to their interior angles as either right or oblique. A right triangle is one in which one of the angles is 90°, and it is represented by two line segments forming a square at the vertex that forms the right angle. The hypotenuse is a right triangle's longest edge, the one opposite the right angle. Any triangle that is not a right triangle is considered an oblique triangle, which can be either obtuse or acute. An obtuse triangle has one angle greater than 90°, whereas an acute triangle has all angles less than 90°.