CK12 - Geometry

2. You can constructthe anglebisectorsof the anglesby first designatingthe angleby selectingthe appro-

priatevertices(e.g.,to selectthe angleat vertex , selectpoints , and in order)and then
choosingConstructAngleBisectorfrom the Constructmenu.Afterbisectingtwo angles,constructthe point
of intersectionby selectingeachanglebisectorand choosingIntersectionfrom the Constructmenu.(Recall
from our proofof the concurrencyof anglebisectorstheoremthat we only needto bisecttwo of the angles
to find the incenter.)

3. You are now readyto constructthe circle.Recallthat the radiusof the circlemustbe the distancefrom
   to eachside – our figureabovedoesnot includethat segment.However, we do not needto construct
   the perpendicularline segmentsas we did to proveTheorem5-7. Sketchpadwill measurethe distancefor
   us.


4. To measurethe distancefrom to eachside,selectpoint and one side of the triangle.Choose
   Distancefrom the Measuremenu.This will give you the radiusof your circle.


5. We are now readyto constructthe circle.Selectpoint and the distancefrom to the side of the
   triangle.Select“Constructcircleby center+ radius”from the Constructmenu.This will give the inscribed
   circlewithinthe triangle.

LessonSummary

In this lessonwe: