Definition
A triangle is a polygon with exactly three sides, three vertices, and three angles. The sum of all three angles in a triangle is always 180 degrees.
The word "triangle" comes from "tri" meaning three and "angle." Every triangle has three corners and three straight sides connecting them.
Examples
- A triangle with sides of 3, 4, and 5 is a right triangle.
- A triangle with all sides equal is called equilateral.
- Road yield signs are shaped like triangles.