Triangle

This may refer to a three sided figure or a musical instrument of the same shape.

When calculating the dimensions and angles of a right triangle, the three sides of it can be defined as the "outer," the "acute," and the "hypotenuse." If certain dimensions and angles of the triangle are known, the other sides and angles can be calculated by comparing the relationships to mathematical charts that define the corresponding ratios that are attributed to those angles and lengths. These relationships bear the terms of sine (outer divided by hypotenuse), cosine (acute divided by hypotenuse), and tangent (outer divided by the acute).