

Plane Geometry: Ptolemy's Theorems and Problems






Ptolemy's Theorem.
Cyclic quadrilateral 


Cyclic
Quadrilateral: Ratio of the Diagonals



Cyclic Quadrilateral.



Jigsaw Puzzle
Ptolemy's Theorem.
22 Piece Polygons. 


Problem 483.
Square, Angle, 90 degrees, Measurement, Ptolemy's theorem. 


Problem 478.
Triangle, Sides, Circumradius, Circumcenter, Circumcircle, Ptolemy's
theorem. 


Problem 474.
Parallelogram, Diagonal, Circle, Vertex, Ptolemy's theorem. 


Proposed Problem 330.
Cyclic quadrilateral, Perpendicular diagonals, Area, Circumcenter,
Ptolemy's theorem. 


Proposed Problem 301.
Tangents to a circle, Secants, Square, Ptolemy's theorem. 


Proposed Problem 300.
Tangents to a circle, Secants, Square, Ptolemy's theorem. 


Proposed Problem 291.
Triangle, Circle, Circumradius, Perpendicular, Ptolemy's theorem. 


Proposed Problem 261.
Regular Pentagon inscribed in a circle, sum of distances, Ptolemy's
theorem.



Proposed Problem 256.
Equilateral Triangle, Circumcircle, Point, Vertices, Distances,
Ptolemy's theorem.



Proposed Problem 63:
Heptagon Regular, Side and Diagonals,
Ptolemy's theorem. 






