# Carlyle circle

> English word · Noun

## Definitions
1. A certain circle in a coordinate plane associated with a quadratic equation, having the property that the solutions of the equation are the horizontal coordinates of the intersections of the circle with the horizontal axis.

## Etymology
The idea of using such a circle to solve a quadratic equation is attributed to Thomas Carlyle (1795–1881).

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/carlyle-circle