Geometry: Perimeter, Semiperimeter, Theorems and Problems- Table of Content

Geometry Problem 1578: Find the Area of a Bicentric Quadrilateral with Perpendicular Extensions of Opposite Sides!.

Geometry Problem 1510 and Poem.
Congruence of Triangles, Perimeter, Measurement. Difficulty Level: High School.

Geometry Problem 1037.
Triangle, Three equal Incircles, Tangent lines, Inradius, Length.

Geometry Problem 1036.
Triangle, Three equal Incircles, Tangent lines, Inradius, Equal Inradii.

Geometry Problem 1034.
Triangle, Three equal Incircles, Tangent lines, Isoperimetric triangles, Equal perimeter.

Geometry Problem 754.
Equilateral Triangle, Center, Angle, 60 Degrees, Perimeter.

Geometry Problem 735.
Triangle, Altitude, Perpendicular, Semiperimeter of the Orthic Triangle, Congruence.

Geometry Problem 686.
Triangle, Three Excircles, Tangency points, Tangent lines, Semi-perimeter, Congruence.

Geometry Problem 684: Outer Nagel Point.
Triangle, Excircles, Incircle Tangency points, Concurrent lines, Semi-perimeter, Ceva theorem.

Geometry Problem 683: Nagel Point.
Triangle, Excircles, Tangency points, Concurrent lines, Semi-perimeter, Ceva theorem.

Problem 531.
Triangle, Angle Bisector, Midpoint, Parallel, Perimeter, Semiperimeter.

Proposed Problem 386.
Triangle, Angle bisector, Perpendicular, Parallel, Semiperimeter, Congruence.

Proposed Problem 385.
Triangle, Angle bisector, Perpendicular, Parallel, Semiperimeter.

Proposed Problem 384.
Triangle, Angle bisector, Perpendicular, Parallel, Semiperimeter.

Proposed Problem 346.
Equal circles, Tangents, Hexagon, Semiperimeter.

Proposed Problem 345.
Equal circles, Tangents, Concurrent lines, Hexagon, Semiperimeter.

Proposed Problem 344.
Quadrilateral, Extension of sides, Circle, Tangent, Semiperimeter.

Proposed Problem 343.
Hexagon, Inscribed circle, Tangent, Semiperimeter.

Proposed Problem 342.
Pentagon, Inscribed circle, Tangent, Semiperimeter.

Proposed Problem 341.
Triangle, Inscribed circle, Tangent, Semiperimeter.

Proposed Problem 202. Right Triangle, Incircle, Excircles relatives to catheti, Points of Tangency, Exradius, Semiperimeter.

Proposed Problem 201. Right Triangle, Excircles, Points of Tangency, Exradius, Semiperimeter.

Proposed Problem 194. Area of a Triangle, Semiperimeter, Exradius.

Proposed Problem 193. Area of a Triangle, Semiperimeter, Inradius.

Proposed Problem 146. Varignon's Theorem: Quadrilateral, Midpoints, Parallelogram, Area, Perimeter.

Proposed Problem 141. Triangle, Incircle, Tangent , Parallel, Perimeters.

Proposed Problem 140. Triangle, Excircle, Tangent, Semiperimeter.

Proposed Problem 139. Triangle Area, Orthic Triangle, Semiperimeter, Circumradius.

Proposed Problem 61:
Triangle, Trisection of Sides, Perimeter.

Problem 51: Fagnano's Problem
Inscribed Triangle with the Minimum Perimeter.

Semiperimeter and excircles of a triangle.

Semiperimeter and incircle of a triangle.

Semiperimeter, incircle and excircles of a triangle.

Heron's Formula.
Key facts and a purely geometric step-by-step proof. Perimeter, Semiperimeter.