A triangle is a three sided geometric shape. The shape forms a basis for the subject of trigonometry and is used throughout mathematics and programming.
The law of sines is an equation that relates the three sides of a triangle with the three angles of a triangle using the sine function.
The law of cosines is a more general form of pythagoreans theorem that relates the squares of the sides together using the cosine function.
A right triangle is a triangle where one of the three angles is a perpendicular angle. There are three sides of the right triangle: the adjacent, opposite, and hypotenuse sides.
The area of a triangle is given by one half multiplied by its width and height.
The area between two vectors is given by the magnitude of their cross product. This formula is a generic way to find the area of any triangle given three points.