Recent Additions 4, Theorems and Problems, Plane Geometry

Geometry Theorems and Problems - Recent Additions (Page 4 of 15)

Problem 560.
Triangle, Cevian, Incenter, Incircle, Perpendicular, Tangent.

Problem 559.
Triangle, Cevian, Incenters, Angle, 90 Degrees.

Problem 558.
Quadrilateral, Trisection, Sides, Wittenbauer Parallelogram, Area, Auxiliary Lines.

Problem 557.
Quadrilateral, Midpoints, Sides, Varignon Parallelogram, Area, Auxiliary Lines.

Problem 556.
Quadrilateral, Diagonal, Angles, Auxiliary Lines.

Problem 555.
Parallel lines, Angle Sums.

Problem 554.
Concave Quadrilateral, Angles, Sum.

Problem 553.
Quadrilateral, Angles, Sum.

Problem 552.
Parallel lines, Transversal, Angle Sums.

Problem 551.
Parallel lines, Transversal, Angle Sums.

Problem 550.
Parallel lines, Transversal, Angle Sums.

Problem 549.
Parallel lines, Transversal, Angle Sums.

Problem 548.
Triangle, Transversal, Four Circumcircles, Circumcenters, Concyclic Points, Similarity.

Problem 547.
Triangle, Transversal, Four Circumcircles, Concurrency.

Circumcircle Index.

Problem 546.
Triangle, Angle Trisectors, 60 Degrees, Equilateral triangle.

Problem 545.
Acute Triangle, Squares, Altitudes, Area, Measure.

Problem 544.
Right Triangle, Altitude, Median, Equal angles, Measure.

Geometry Problems 341 - 350.
Triangle, Quadrilateral, Pentagon, Hexagon, Inscribed circle, Tangent, Semiperimeter, Equal circles, Concurrent lines, Altitude, Concyclic Points, Cevian, Incircle.

Problem 543.
Right Triangle, Altitude, Angle Bisector, Median.

Problem 542.
Right Triangle, Altitude, Angle Bisector, Perpendicular, 90 Degrees.

Problem 541.
Right Triangle, Altitude, Angle Bisector, Congruence.

Geometry Problems 331 - 340.
Square, Circle, Similarity, Cyclic quadrilateral, Trapezoid, Triangle, Isosceles, Circumcircle, Incircle, Diagonal, Tangent, Perpendicular, Parallel, Concyclic points.

Geometry Problems 321 - 330.
Triangle, Square, Circle, Area, Cyclic quadrilateral, Tangent, Incenter, Circumcenter, Excircle, Midpoint, Altitude, Collinearity, Concurrence, Isosceles, Equilateral, Parallel, Perpendicular, Diameter, Concyclic.

Geometry Problems 311 - 320.
Circle, Semicircle, Chord, Diameter, Tangent, Cyclic quadrilateral, Geometric mean, Square, Right triangle, Altitude, Collinearity, Circumcircle, Incenter, Excenter.

Geometry Problems 301 - 310.
Circle, Tangent, Secant, Square, Triangle, Angle Bisector, 45, 60, 90, 120 Degrees, Side, Nonagon, Midpoint, Arc, Diagonal, Semicircle.

Geometry Problems 231 - 240.
Triangle, Quadrilateral, Square, Parallelogram, Trapezoid, Altitude, Distances, Midpoint, Perpendicular, Transversal.

Problem 540.
Right Triangle, Square, Parallel, Perpendicular, Dissection, Area, Pythagoras.

Geometry Problems 291 - 300.
Triangle, Circle, Square, Congruence, Similarity, Circumradius, Perpendicular, Parallel, Secant, Tangent, Chord, Intersection, Midpoint, Radius, Angle.

Problem 539.
Right Triangle, Square, Parallel, Perpendicular, Dissection, Area, Pythagoras.

Geometry Problems 281 - 290.
Triangle, Square, Circle, Octagon, Congruence, Isosceles, Equilateral, 90 Degrees, Circular Sector, Semicircle, Tangent, Radius, Diameter, Harmonic Mean.

Problem 538.
Triangle, Perpendicular Bisector, Circumcircle, Midpoint.

Problem 537.
Rectangle, Midpoints, Diagonal, Angle Bisector.

Problem 536.
Intersecting Circles, Chord, Perpendicular.

Problem 535.
Sawayama - Thebault's theorem: Triangle, Incircle, Circle, Center, Tangent, Collinear.

Problem 534.
Right Triangle, Squares, Perpendicular, Dissection, Areas.

Geometry Problems 271 - 280.
Circle, Quadrilateral, Square, Tangent, Cube, Triangle, Isosceles, Area, 90-80-80-20 Degrees, Circumcircle, Sagitta, Inradius, Chord, Perpendicular.

Geometry Problems 261 - 270.
Regular Polygon, Pentagon, Hexagon, Circle, Tangent, Similarity, Triangle, Hypotenuse, Catheti, Geometric Mean, Altitude, Projection, Fractional Exponent.

Problem 533.
Euclid's Elements, Book XIII, Proposition 10. One page visual illustration.

Geometry Problems 251 - 260.
Parallelogram, Rectangle, Triangle, Square, Circle, Area, Side, Equilateral, Isosceles, Centroid, Distance, Vertex, Circumcircle, Incircle, Tangent, Diagonal.

Brahmagupta Theorem and Problems - Index
Brahmagupta (598–668) was an Indian mathematician and astronomer who discovered a neat formula for the area of a cyclic quadrilateral.

Solid Geometry: Morphing Platonic Solids. Sacred geometry, Video and News.

Problem 532.
Triangle, Circumcircle, Equal Angles, Perpendicular, Area.

Ptolemy's Theorems and Problems - Index.

Semiperimeter, Perimeter Index.
Theorems and Problems.

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

Geometry Problems 241 - 250.
Triangle, Quadrilateral, Congruence, Area, Parallelogram, Square, Diagonal, Center, Napoleon, Median, Midpoint.

Problem 530.
Cyclic Quadrilateral, Diagonal, Diameter, Perpendicular, Congruence.

Problem 529.
Right Trapezoid, Circle, Diameter.

Problem 528.
Triangle, Medians, Perpendicular, Measurement.

Problem 527.
Circle, Tangent, Secant, Chord, Midpoint, Measurement.

Problem 526.
Equilateral Triangle, Circumcircle, Chord, Measurement.

Geometry Problems 221 - 230.
Isosceles, Equilateral triangle, Viviani's theorem, Altitude, Distances, Regular Polygon, Apothem, Centroid, Midpoint, Perpendicular, Transversal..

Problem 525.
Circles, Diameter, Tangent, Radius, Congruence, Measurement.

Problem 524.
Circle, Equilateral Triangles, Midpoint, Side, Measurement.

Problem 523.
Tangent Circles, Diameter Perpendicular, Collinearity.

Problem 522.
Right Triangle, Circle, Diameter, Tangent.

Problem 521.
Triangle with three Squares, Altitude, Rectangle, Area.