Pronunciation: /pəˈrɛn θə sɪs/ ?

-- plural is parentheses

Parentheses are marks used to group operations.[1]

Parentheses are always used in pairs. The left parenthesis looks like: (. The right parenthesis looks like: ).

The parentheses are used to group operations in math. For example, the expression 5·4+2 evaluates to 22. Using the order of operations, we first multiply 5 and 4 to get 20, and then add 2 to get 22.

However, if we use parentheses to write the expression as 5·(4+2), the value of the expression changes. The parenthesis tells us to add 4 to 2 before multiplying by 5. Adding 4 and 2 gives us 6. When we then multiply by 5 we get 30.


  1. parenthesis. WordNet. Princeton University. (Accessed: 2011-01-08).
  2. Keigwin, H. W.. Principles of Elementary Algebra, pg 4. Ginn & Company, 1886. (Accessed: 2010-01-12).
  3. Bettinger, Alvin K. and Englund, John A.. Algebra and Trigonometry, pg 17-18. International Textbook Company, January 1963. (Accessed: 2010-01-12).

Cite this article as:

Parenthesis. 2009-12-23. All Math Words Encyclopedia. Life is a Story Problem LLC.


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Revision History

2009-12-23: Added "References" (McAdams, David.)
2008-09-02: Added 'More Information' (McAdams, David.)
2007-07-12: Initial version (McAdams, David.)

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