# Parenthesis

Pronunciation: /pəˈrɛn.θə.sɪs/ Explain

-- plural is parentheses

Parentheses are marks used to group operations.[2]

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.

### References

1. McAdams, David E.. All Math Words Dictionary, parenthesis. 2nd Classroom edition 20150108-4799968. pg 135. Life is a Story Problem LLC. January 8, 2015. Buy the book
2. Keigwin, H. W.. Principles of Elementary Algebra. pg 4. www.archive.org. Ginn & Company. 1886. Last Accessed 12/3/2018. http://www.archive.org/stream/principlesofelem00dupurich#page/4/mode/1up/search/parenthesis. Buy the book
3. Bettinger, Alvin K. and Englund, John A.. Algebra and Trigonometry. pg 17-18. www.archive.org. International Textbook Company. January 1963. Last Accessed 12/3/2018. http://www.archive.org/stream/algebraandtrigon033520mbp#page/n18/mode/1up. Buy the book

McAdams, David E. Parenthesis. 4/27/2019. All Math Words Encyclopedia. Life is a Story Problem LLC. http://www.allmathwords.org/en/p/parenthesis.html.

### Revision History

4/27/2019: Changed equations and expressions to new format. (McAdams, David E.)
12/21/2018: Reviewed and corrected IPA pronunication. (McAdams, David E.)