right-an·gled tri·ang·le
noun/ˌraɪt æŋɡld ˈtraɪæŋɡl/
/ˌraɪt æŋɡld ˈtraɪæŋɡl/
(especially British English) (North American English usually right triangle)
- a flat shape with three straight sides and one right angle
enlarge image直角三角形