Example image of eyePlorer eyePlorer map for 'Altitude (triangle)': Geometry Line (geometry) Perpendicular Right angle Triangle Vertex (geometry) Congruence Midpoint Area Right triangle If and only if Centroid Circumscribed circle Euler line Nine-point circle Complement (mathematics) Isogonal conjugate Orthocentric system Barycentric coordinates (mathematics) Trilinear coordinates Pedal triangle Homothetic transformation Giulio Carlo de' Toschi di Fagnano Equilateral triangle Incircle and excircles of a triangle Hypotenuse Wolfram Demonstrations Project De Longchamps point Fuhrmann circle Viviani's theorem Cevian Fagnano's problem Triangle center Concurrent lines Medial triangle Conway triangle notation Nine-point hyperbola Johnson circles Centre (geometry) Stewart's theorem Complete quadrangle Height Simson line Heronian triangle Heron's formula Menelaus' theorem Pythagorean theorem Acacia Fraternity Altitude (disambiguation) Height (disambiguation)