Pronunciation: /əˈkyut ˈæŋ gəl/ ?
Figure 1: Acute angles measure < 90°
|Manipulative 1: Classes of angles. Created
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are divided into four classes according to their measure. An acute angle
is an angle that measures less than 1/4 of a full
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- acute angle. merriam-webster.com. Encyclopedia Britannica. (Accessed: 2009-12-21). http://www.merriam-webster.com/dictionary/acute angle.
- Keller, Samuel Smith. Mathematics for Engineering Students, Plane and Solid Geometry, pg 2. D. Van Nostrand Company, 1908. (Accessed: 2010-01-02). http://www.archive.org/stream/mathengineer00kellrich#page/2/mode/1up/search/acute.
- Casey, John, LL.D., F.R.S.. The First Six Books of the Elements of Euclid, 10th Edition, pg 4. Casey, John, LL.D. F.R.S.. Hodges, Figgis & Co., 1890. (Accessed: 2010-01-02). http://www.archive.org/stream/firstsixbooksofe00caseuoft#page/4/mode/1up/search/acute.
Cite this article as:
Acute Angle. 2010-01-01. All Math Words Encyclopedia. Life is a Story Problem.org. http://www.allmathwords.org/en/a/acuteangle.html.
2010-01-01: Added reference to Euclid's Elements, Expanded table of angle classes. (McAdams, David.
2008-09-16: Changed text on classes of angles to a table. Changed images 2 and 3 to one manipulative (McAdams, David.
2008-03-03: Revised other resources, added reference to radians (McAdams, David.
2007-07-16: Expanded keyword 'acute' to include 'angle' (McAdams, David.
2007-07-12: Initial version (McAdams, David.