TriangleConstruct

TriangleConstruct[tri, type] gives the specified type of construct for the triangle tri.

Examples

Centroid of a triangle:

tri = Triangle[{{0, 0}, {1, 0}, {0.5, 1}}];
TriangleConstruct[tri, "Centroid"]

Circumcircle:

TriangleConstruct[tri, "Circumcircle"]

Incircle:

TriangleConstruct[tri, "Incircle"]

Please visit the official Wolfram Language Reference for more details.