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How to Find Circumcircle and Circumcenter with GeoGebra
     You can use GeoGebra to find the circumcircle and circumcenter of a triangle. 
     GeoGebra Instruction 1
- 1.
-          Open         Algebra ViewandGraphics ViewunderViewinMenu.
- 2.
-          Make         a         triangle         with         the         vertices         ,         ,         and                by         clicking         Polygon. Then, you need to click on three points in Graphics Viewwhere you want the vertices of the triangle to be. Finally, complete the triangle by clicking on the point that you started with.
- 3.
-          Click         on         Perpendicular Bisectorby first clicking tool number 4, then tool number 3 in the drop-down list. 
- 4.
- Construct the perpendicular bisector of , the perpendicular bisector of and the perpendicular bisector of by clicking on the sides of .
- 5.
-          Click         Intersectby first clicking tool number 4, then tool number 4 in the drop-down list, and use it to find the point of intersection of two perpendicular bisectors. The point is the circumcenter. 
- 6.
-          Click         Circle with Center through Pointto construct a circle with the circumcenter as the center, and one of the vertices of the triangle as the point. You will see that the circle actually touches all vertices even though you just clicked one corner. You’ve drawn the circumcircle!