› algebra an equation (= mathematical statement) that includes an unknown value multiplied by itself only once, and does not include an unknown value multiplied by itself more than once; an equation that can be expressed as ax²+bx+c=0, when a does not equal zero

(Definition of quadratic equation noun from the Cambridge Academic Content Dictionary
© Cambridge University Press)

You are looking at an entry to do with Calculations & calculating, but you might be interested in these topics from the **Mathematics & arithmetic** topic area:

- Addition, subtraction, multiplication & division
- Averages
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- Geometry: bends, loops & curves
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- Numbers: cardinal, including nought & zero
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