---
tag: 0CTNFGYMM2
kind: concept
name: Triangle
msc: [51M04]
sources:
  - url: https://en.wikipedia.org/wiki/Triangle
    locator: lead section
same_as:
  wikidata: Q19821
  wikipedia: Triangle
---

## Summary

A triangle is a polygon with three vertices and three sides. Its three vertices are points that do not lie on one line, and its sides are the segments that join them in pairs.