3. __, __
- Drawan equilateraltrianglewith one set of exteriorangleshighlighted.Whatis the measureof eachex-
teriorangle?Whatis the sum of the measuresof the threeexterioranglesin an equilateraltriangle?
- Recallthat a regularpolygonis a polygonwith congruentsidesand congruentangles.Whatis the measure
of eachinterioranglein a regularoctagon?
- How can you use your answerto 5 to find the measureof eachexterioranglein a regularoctagon?Draw
a sketchto justifyyour answer.
- Use your answerto 6 to find the sum of the measuresof the exterioranglesof an octagon.
- Completethe followingtableassumingeachpolygonis a regularpolygon.Note:This is similarto a previous
exercisewith morecolumns—youcan use your answerto that questionto help you with this one.
Sum of measures
of exteriorangles
Measureof each
exteriorangle
Measureof each
interiorangle
Sum of measures
of interiorangles
RegularPolygonNumberof sides
name
triangle
4
5
6
7
octagon
decagon
