True.
False.
9 is falsesincethe threesideswouldnot makea triangle.To makethe statementtrue, it shouldsay:
“An obtusetrianglehas exactlyone obtuseangle.”
ClassifyingPolygons
LearningObjectives
- Definepolygons.
- Understandthe differencebetweenconvexand concavepolygons.
- Classifypolygonsby numberof sides.
- Use the distanceformulato find side lengthson a coordinategrid.
Introduction
As you progressin your studiesof geometry, you can examinedifferenttypesof shapes.In the last lesson,
you studiedthe triangle,and differentwaysto classifytriangles.This lessonpresentsothershapes,called
polygons. Thereare manydifferentwaysto classifyand analyzetheseshapes.Practicetheseclassification
proceduresfrequentlyand they will get easierand easier.
DefiningPolygons
Nowthat you knowwhata triangleis, you can learnaboutothertypesof shapes.Trianglesbelongto a
largergroupof shapescalledpolygons.A polygonis any closedplanarfigurethat is madeentirelyof line
segmentsthat intersectat their endpoints.Polygonscan haveany numberof sidesand angles,but the sides
can neverbe curved.
The segmentsare calledthesidesof the polygons,and the pointswherethe segmentsintersectare called
vertices. Notethat the singularof verticesisvertex.