# Etiology of "Quadratic" applied to Quad Formula

**URL:** <https://boards.straightdope.com/t/etiology-of-quadratic-applied-to-quad-formula/199219>\
**Category:** Factual Questions\
**Created:** [September 2, 2003, 10:07pm UTC](https://boards.straightdope.com/t/etiology-of-quadratic-applied-to-quad-formula/199219 "2003-09-02T22:07:52Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Ringo847](https://avatars.discourse-cdn.com/v4/letter/r/3ab097/32.png) [@Ringo847](https://boards.straightdope.com/u/Ringo847)\
**Post date:** [September 2, 2003, 10:07pm UTC](https://boards.straightdope.com/t/etiology-of-quadratic-applied-to-quad-formula/199219/1 "2003-09-02T22:07:52Z")

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How did the quadratic equation and formula get its names? If “quad” means 4, how does this number apply to the equation? Was “Quad” once used to mean 2?

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**Author:** ![MC\_Master\_of\_Ceremonies](https://avatars.discourse-cdn.com/v4/letter/m/bb73d2/32.png) [@MC\_Master\_of\_Ceremonies](https://boards.straightdope.com/u/MC_Master_of_Ceremonies)\
**Post date:** [September 2, 2003, 10:19pm UTC](https://boards.straightdope.com/t/etiology-of-quadratic-applied-to-quad-formula/199219/2 "2003-09-02T22:19:49Z")

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‘Quad’ as in ‘square’ as in squared, simlairly cubic equations start with and x cubed term.

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**Author:** ![wolf\_meister](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolf_meister/32/15202_2.png) [@wolf\_meister](https://boards.straightdope.com/u/wolf_meister)\
**Post date:** [September 3, 2003, 12:44am UTC](https://boards.straightdope.com/t/etiology-of-quadratic-applied-to-quad-formula/199219/3 "2003-09-03T00:44:08Z")

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And if you want to see the quadratic formula or solve quadratics, here’s a link:  
[http://www.1728.com/quadratc.htm](http://www.1728.com/quadratc.htm)

Here’s a link for solving cubic equations  
[http://www.1728.com/cubic.htm](http://www.1728.com/cubic.htm)

And relevant to the OP, a 4th power equation is called a “quartic” (since you were wondering when that ‘4’ would enter the picture).

And yes there’s a calculator for those too:  
[http://www.1728.com/quartic.htm](http://www.1728.com/quartic.htm)

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**Author:** ![Earl\_Snake-Hips\_Tucker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/earl_snake-hips_tucker/32/3269_2.png) [@Earl\_Snake-Hips\_Tucker](https://boards.straightdope.com/u/Earl_Snake-Hips_Tucker)\
**Post date:** [September 3, 2003, 2:14am UTC](https://boards.straightdope.com/t/etiology-of-quadratic-applied-to-quad-formula/199219/4 "2003-09-03T02:14:24Z")

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As a side question, I’d also like to know the etymology of “etiology” as it relates to quadratic equations.😃