quadratic equation

English

Noun

quadratic equation (plural quadratic equations)

1. (algebra) A polynomial equation of the second degree; an equation that can be rearranged in standard form as $ax^{2}+bx+c=0$, where $x$ is an unknown value, and $a$, $b$, and $c$ are known numbers, where $a$ does not equal zero.

   Coordinate terms: linear equation, cubic equation

   • 2015 September 8, Katie Everson, “Why I've written a book for teenagers about taking drugs”, in The Guardian‎^[1]:

     When I was seven years old at a new school, I cried all day, every day. When I was 14 years old, I cried in maths lessons. An improvement, I guess. It wasn’t that I was bad at maths; I knew my way around a quadratic equation, let me tell you.

   • 2018 November 25, Kevin McKenna, “Remote island pub for sale ... just don’t expect a quiet life”, in The Guardian‎^[2]:

     The arid argot of the estate agent’s schedule becomes obsolete when the task is to sell a pub-restaurant at the edge of a Highland wilderness. It’s like trying to describe the glory of the Lake District with a quadratic equation.

   • 2020 February 5, Kenneth Chang, Jonathan Corum, “This Professor’s ‘Amazing’ Trick Makes Quadratic Equations Easier”, in The New York Times‎^[3]:

     The quadratic equation has frustrated math students for millenniums. […] If, while watching the Super Bowl, you had wanted to estimate how far a pass thrown by Patrick Mahomes traveled through the air, you would have been solving a quadratic equation.

   • 2024 April 8, Lydia Wang, Morgan Sullivan, Rachel Varina, “24 Best Hinge Prompts to Actually Help Your Matches Get to Know You”, in Cosmopolitan‎^[4]:

     If there’s one skill we absolutely should have been taught in school, it's how to craft the perfect dating app profile. I mean, if I can still remember the quadratic equation, surely I should have been schooled in the art of snagging a date. But alas, our education system seems to think finding our soulmates isn't as essential as algebra.

Translations

second-degree equation

• Armenian: քառակուսի հավասարում (kʻaṙakusi havasarum)
• Catalan: equació quadràtica f
• Chinese:

  Mandarin: 二次方程 (zh) (èr-cì fāngchéng)

• Czech: kvadratická rovnice f
• Danish: andengradsligning c
• Dutch: tweedegraadsvergelijking f, vierkantsvergelijking f
• Finnish: toisen asteen yhtälö
• French: équation du second degré (fr) f
• German: quadratische Gleichung f
• Greenlandic: andengradsligningi
• Hungarian: másodfokú egyenlet (hu)
• Italian: equazione di secondo grado f, equazione quadratica f
• Japanese: 二次方程式 (ja) (niji hōteishiki)
• Korean: 이차 방정식 (icha bangjeongsik)
• Maori: whārite pūrua
• Polish: równanie kwadratowe n
• Portuguese: equação quadrática f, equação do segundo grau f
• Romanian: ecuație de gradul al doilea (ro) f, ecuație pătratică f
• Russian: квадра́тное уравне́ние (ru) n (kvadrátnoje uravnénije)
• Spanish: ecuación cuadrática f, ecuación de segundo grado f
• Tagalog: dawaking tumbasan
• Thai: สมการกำลังสอง
• Turkish: ikinci dereceden denklem, ikinci derece denklem
• Urdu: دو ضربی مساوات f (do-zarbī musāvāt)

Further reading

• “quadratic equation, n.”, in OED Online ⁠, Oxford, Oxfordshire: Oxford University Press, launched 2000.
• “quadratic equation”, in Merriam-Webster Online Dictionary, Springfield, Mass.: Merriam-Webster, 1996–present.
• “quadratic equation”, in The American Heritage Dictionary of the English Language, 5th edition, Boston, Mass.: Houghton Mifflin Harcourt, 2016, →ISBN.