Centers of a Triangle by Clio Hartzer
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This applet demonstrates the four basic 'centers' of a triangle (centroid, circumcenter, incenter, orthocenter) and their relationships, along with midsegments. Constructed using GeoGebra commands like Segment, AngularBisector, Line, OrthogonalLine, LineBisector, Intersect, Circle, and Angle, it involves points, sides, angle bisectors, altitudes, perpendicular bisectors, circumcircle, incircle, etc., making it suitable for high school geometry education and construction learning.
GeoGebra Commands & Parameters
Segment(PointC, PointB) → SideASegment(PointA, PointC) → SideBSegment(PointB, PointA) → SideCAngularBisector(PointA, PointC, PointB) → AngleBisLineB2Line(PointC, PointB) → LineAOrthogonalLine(PointA, LineA) → AltitudeB1Line(PointA, PointC) → LineBOrthogonalLine(PointB, LineB) → AltitudeB3Line(PointB, PointA) → LineCOrthogonalLine(PointC, LineC) → AltitudeB2LineBisector(SideC) → PerpBisB1LineBisector(SideB) → PerpBisB3LineBisector(SideA) → PerpBisB2Intersect(PerpBisB1, PerpBisB2) → CircumcenterSegment(Circumcenter, PointC) → Circum1Segment(Circumcenter, PointA) → Circum2Segment(Circumcenter, PointB) → Circum3Circle(Circumcenter, Circum1) → CircumcircleIntersect(PerpBisB2, SideA) → Midpoint1Intersect(PerpBisB1, SideC) → Midpoint2Intersect(PerpBisB3, SideB) → Midpoint3Segment(Circumcenter, Midpoint3) → PerpBis1Segment(Circumcenter, Midpoint1) → PerpBis2Segment(Circumcenter, Midpoint2) → PerpBis3AngularBisector(PointB, PointA, PointC) → AngleBisLineB1AngularBisector(PointC, PointB, PointA) → AngleBisLineB3Intersect(AngleBisLineB1, AngleBisLineB2) → IncenterLineOrthogonalLine(IncenterLine, LineC) → IncenterB1OrthogonalLine(IncenterLine, LineA) → IncenterB2OrthogonalLine(IncenterLine, LineB) → IncenterB3Intersect(IncenterB1, SideC) → IncenterA1Intersect(IncenterB3, SideB) → IncenterA2Intersect(IncenterB2, SideA) → IncenterA3Intersect(AngleBisLineB1, SideA) → AngBisA1Intersect(AngleBisLineB3, SideB) → AngBisA2Segment(AngBisA1, PointA) → AngBisect1Intersect(AngleBisLineB2, SideC) → AngBisA3Segment(AngBisA3, PointC) → AngBisect2Segment(AngBisA2, PointB) → AngBisect3Segment(IncenterLine, IncenterA1) → Incenter1Segment(IncenterLine, IncenterA3) → Incenter2Segment(IncenterLine, IncenterA2) → Incenter3Intersect(AngBisect1, AngBisect2) → IncenterCircle(Incenter, Incenter1) → IncircleAngle(Incenter, IncenterA2, PointA) → IncenterAAngle(Incenter, IncenterA1, PointB) → IncenterBAngle(Incenter, IncenterA3, PointC) → IncenterCSegment(PointB, Midpoint3) → Median1Segment(Midpoint2, PointC) → Median2Segment(PointA, Midpoint1) → Median3Intersect(Median1, Median2) → CentroidIntersect(AltitudeB1, AltitudeB2) → OrthocenterIntersect(AltitudeB2, LineC) → AltitudeA1Angle(Orthocenter, AltitudeA1, PointB) → AltitudeAIntersect(AltitudeB1, LineA) → AltitudeA3Angle(Orthocenter, AltitudeA3, PointC) → AltitudeBIntersect(AltitudeB3, LineB) → AltitudeA2Angle(Orthocenter, AltitudeA2, PointA) → AltitudeCSegment(PointC, AltitudeA1) → Altitude1Segment(PointA, AltitudeA3) → Altitude2Segment(PointB, AltitudeA2) → Altitude3Angle(Circumcenter, Midpoint2, PointB) → PerpBisAAngle(Circumcenter, Midpoint1, PointC) → PerpBisBAngle(Circumcenter, Midpoint3, PointA) → PerpBisCSegment(Midpoint2, PointA) → MidpointC1Segment(Midpoint2, PointB) → MidpointC2Segment(PointB, Midpoint1) → MidpointA1Segment(Midpoint1, PointC) → MidpointA2Segment(PointC, Midpoint3) → MidpointB1Segment(Midpoint3, PointA) → MidpointB2Angle(AngBisA3, PointB, AngBisA2) → AngleBisA1Angle(AngBisA2, PointB, PointC) → AngleBisA2Angle(PointC, PointA, AngBisA1) → AngleBisB1Angle(AngBisA1, PointA, PointB) → AngleBisB2Angle(PointB, PointC, AngBisA3) → AngleBisC1Angle(AngBisA3, PointC, PointA) → AngleBisC2Segment(Midpoint2, Midpoint1) → MidBSegment(Midpoint1, Midpoint3) → MidCSegment(Midpoint3, Midpoint2) → MidAOrthogonalLine(PointA, LineA) → AltLineAOrthogonalLine(PointC, LineC) → AltLineCOrthogonalLine(PointB, LineB) → AltLineBLine(Circumcenter, Orthocenter) → EulerLineAngle(PointA, PointC, PointB) → VertCAngle(PointC, PointB, PointA) → VertAAngle(PointB, PointA, PointC) → VertB
AI Drawing Prompt Reference
Draw a triangle and construct its three perpendicular bisectors of sides, their intersection is the circumcenter. Connect the circumcenter to the vertices to form the circumcircle. Then, draw the three angle bisectors, their intersection is the incenter. Connect the incenter to the sides to form the incircle. Also, draw the three altitudes, their intersection is the orthocenter. Finally, connect the midpoints of the sides to show the midsegments and relationships among these centers and segments.
The prompt above was compiled from the original drawing commands and is for reference only.