| a quantity of which a given quantity is the square: The quantities +6 and −6 are square roots of 36 since (+6)×(+6)=36 and (−6)×(−6)=36. |
| square root n. A divisor of a quantity that when squared gives the quantity. For example, the square roots of 25 are 5 and -5 because 5 × 5 = 25 and (-5) × (-5) = 25. |
A number that, when multiplied by itself, will result in a given number. The square root of four is two; the square root of one hundred is ten.
Note: The square roots of many numbers, such as three, are irrational numbers.
| square root
A number that, when squared, yields a given number. For example, since 5 × 5 = 25, the square root of 25 (written √25) is 5. |
square root
in mathematics, a factor of a number that, when multiplied by itself, gives the original number. For example, both 3 and -3 are square roots of 9. As early as the 2nd millennium BC, the Babylonians possessed effective methods for approximating square roots. See root
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