Machu Picchu, Geometry Theorems and Problems, Online Education

Geometry Theorems and Problems - Recent Additions (Page 6 of 15)

Euclidean Geometry

Geometry Problem 988

Geometry Problem 988.
Right Triangle, Cevians, Angles, 30 Degrees, Triple Angle.

Geometry Problem 987

Geometry Problem 987.
Triangle, Circumcircle, Incenter, Chord, Parallel, Circle, Tangent. GeoGebra, HTML5 Animation for Tablets (iPad, Nexus).

Geometry Problem 986

Geometry Problem 986.
Triangle, Median, Midpoint, Equal Angles, 45 Degrees.

Geometry Problem 985

Geometry Problem 985.
Circle, Radius, Perpendicular, Concentric Circles, Congruence, Triangle.

Geometry Problem 984

Geometry Problem 984.
Triangle, Circumcircle, Altitudes, Midpoint, Collinear Points.

Geometry Problem 983

Geometry Problem 983.
Regular Hexagon, A point and six triangles, Areas.

Geometry Problem 982

Geometry Problem 982.
Triangle, Excenters, Excentral Triangle, Circumcenter, Area, Hexagon.

Geometry Problem 981

Geometry Problem 981.
Triangle, Concurrent Cevians, Midpoints, Area, Hexagon.

Geometry problems 971-980

Geometry Problems 971 - 980.
Equilateral Triangle, Rectangle, Circle, Parallel, Reflection, Concurrency, Paallelogram, Orthocenter, Circumcenter.

Geometry Problem 980

Geometry Problem 980.
Equilateral Triangle, Vertices, Three Parallel, Equal Circles, Construction.

Geometry Problem 979

Geometry Problem 979.
Triangle, Cevian, Angle Bisector, Concurrency, 90 Degrees, Perpendicular.

Geometry Problem 978

Geometry Problem 978.
Parallelogram, Diagonal, Transversal, Similarity, Metric Relations.

Geometry Problem 977

Geometry Problem 977.
Acute Triangle, Circumcenter, Orthocenter, Distance, Circumradius, Altitude, Metric Relations.

Geometry Problem 976

Geometry Problem 976.
Isosceles Right Triangle, 45 Degrees, Incenter, Angle Bisector, Hypotenuse.

Geometry Problem 975

Geometry Problem 975.
Isosceles Right Triangle, 45 Degrees, Angle Bisector, Hypotenuse.

Geometry Problem 974

Geometry Problem 974.
'Begonia Theorem', Cevian Triangle, Reflection of a point in a line, Concurrency of Lines. GeoGebra, HTML5 Animation for Tablets.

Geometry Problem 973

Geometry Problem 973.
Three Parallel, Square, Vertices, Distance Between Two Parallel Lines, Side, Metric Relations.

Geometry Problem 972

Geometry Problem 972.
Equilateral Triangle, Vertices, Three Parallel, Equal Circles, Perpendicular Bisector.

Geometry Problem 971

Geometry Problem 971.
Equilateral Triangle, Rectangle, Common Vertex, Sum of Right Triangles Areas.

Geometry Problem 970

Geometry Problem 970.
Equilateral Triangle, Circumcircle, Secant, Metric Relations.

Geometry Problem 969

Geometry Problem 969.
Equilateral Triangle, Rectangle, Common Vertex, Right Triangles Areas.

Geometry Problem 968

Geometry Problem 968.
Equilateral Triangle, Rectangle, Common Vertex, Midpoint.

Geometry Problem 967

Geometry Problem 967.
Three Equilateral Triangles, Midpoints. GeoGebra, HTML5 Animation for Tablets (iPad, Nexus).

Geometry Problem 966

Geometry Problem 966.
Triangle, Cevians, Midpoint, Circumcircle, Circle, Tangent Line, Collinear Points.

Geometry Problem 965

Geometry Problem 965.
Triangle, Cevians, Midpoint, Circumcircle, Circle, Tangent Line, Metric Relations.

Geometry Problem 964

Geometry Problem 964.
Right Triangle, Cevians, Angles, 10, 20, 30 Degrees.

Geometry Problem 963

Geometry Problem 963.
Right Triangle, 30-60-90 Degrees, Angle Bisectors, Metric Relations.

Geometry Problem 962

Geometry Problem 962.
Triangle, Two Cevians, Areas, Equal Products.

Geometry Problem 961

Geometry Problem 961.
Quadrilateral, Trisection, Sides, Sum of Areas.

Geometry Problem 960

Geometry Problem 960.
Quadrilateral, Trisection, Sides, Congruence, Similarity, Triangle.

Geometry Problem 959

Geometry Problem 959.
Triangle, Sides Ratio 4:1, Inradius, Exradius, Cevian, Mean Proportional, Geometric Mean, Metric Relations.

Geometry Problem 958

Geometry Problem 958.
Isosceles Triangle, Altitude, 45 Degrees, Perpendicular, Angle Bisector, Metric Relations.

Geometry Problem 957

Geometry Problem 957.
Equilateral Triangle, Inscribed Circle, Incircle, Circumscribed Circle, Circumcircle, Area, Circular Segment.

Geometry Problem 956

Geometry Problem 956.
Two Equilateral Triangles, Center, Collinear Points, Midpoint, Right Triangle, 30, 60, 90 Degrees.

Geometry Problem 955

Geometry Problem 955.
Quadrilateral, Triangle, Diagonals, Triangle, Angles, 30, 40, 60, 70 Degrees.

Geometry Problem 954

Geometry Problem 954.
Intersecting Circles, Secant, Common Chord, Cyclic Quadrilateral, Angle Bisector.

Geometry Problem 953

Geometry Problem 953.
Intersecting Circles, Secant, Common Chord, Cyclic Quadrilateral, Perpendicular.

Geometry Problem 952

Geometry Problem 952.
Triangle, Incenter, Circumcenter, Three Equal Circles, Tangent Line, Tangent Circles, Collinear Points.

Geometry Problem 951

Geometry Problem 951.
Intersecting Circles, Chord, Diameter, Parallel, Cyclic Quadrilateral, Concyclic Points.

Geometry Problem 950

Geometry Problem 950.
Intersecting Circles, Secant, Cyclic Quadrilateral, Concyclic Points.

Geometry Problem 949

Geometry Problem 949.
Intersecting Circles, Secant, Cyclic Quadrilateral, Concyclic Points.

Geometry Problem 948

Geometry Problem 948.
Intersecting Circles, Secant, Cyclic Quadrilateral, Concyclic Points.

Geometry Problem 947

Geometry Problem 947.
Triangle, Circumcircle, Angle Bisector, Chord, Arc, Parallel.

Geometry Problem 946

Geometry Problem 946.
Triangle, Quadrilateral, Area, Diagonal, Midpoint, Parallel.

Geometry problems 891-900

Geometry Problems 891 - 900.
Triangle, Circle, Parallelogram, Trapezoid, Congruence, Similarity, Metric Relations, Incircle, Rectangle, Square

Geometry Problem 945

Geometry Problem 945.
Triangle, Concurrent Lines, Cevians, Perpendicular, Angle Bisector.

Geometry Problem 944

Geometry Problem 944.
Triangle, Orthocenter, Altitude, Perpendicular, 90 Degrees, Parallel Lines.

Geometry Problem 943

Geometry Problem 943.
Triangle, Incircle, Inscribed Circle, Tangency Points, Parallel, Metric Relations.

Geometry Problem 942

Geometry Problem 942.
Triangle, Circles, Circumcircle, Sagitta, Incircle, Excircle, Inradius, Exradius, Metric Relations.

Problem 941

Geometry Problem 941.
Circles Tangent Externally, Tangent, Secant, Proportion, Angle.

Problem 940

Geometry Problem 940.
Circle, Tangent, Secant, Chord, Parallel, Perpendicular, 90 Degrees, Midpoint.

Problem 939

Geometry Problem 939.
Circle, Tangent, Secant, Chord, Parallel, Midpoint.

Problem 938

Geometry Problem 938.
Cyclic Quadrilateral, Triangle, Circumcircle, Circles, Circumcenter, Circumradius, Distance, Metric Relations.

Problem 937

Geometry Problem 937.
Triangle, Circumcircle, Circles, Tangent, Sides, Midpoint.

Problem 936

Geometry Problem 936.
Circle, Semicircle, Diameter, Tangent, Radius, Chord, Metric Relations.

Problem 935

Geometry Problem 935.
Square, Circle, Center, Perpendicular, Metric Relations.

Problem 934

Geometry Problem 934.
Square, Circle, Center, Perpendicular, Metric Relations.

Problem 933

Geometry Problem 933.
Square, Center, Transversal, Perpendicular, Metric Relations, Congruence.

Problem 932

Geometry Problem 932.
Square, Midpoint, Diagonal, Ratio 3:1, Angle Measure, Congruence.

Problem 931

Geometry Problem 931.
Square, Circle, Semicircle, Diameter, Triangle, Angle, Metric Relations.

Exeter Point

Dynamic Geometry: Exeter Point
Triangle, Median, Circumcircle, Concurrent Lines, Euler Line, GeoGebra, HTML5 Animation for Tablets.

Problem 930

Geometry Problem 930.
Acute Triangle, Altitudes, Circles, Diameter, Angle, Measure.

Problem 929

Geometry Problem 929.
Triangle, Orthocenter, Circumcircle, Reflection, Concurrency.

Problem 928

Geometry Problem 928.
Triangle, Midpoint, Median, Cevian, Concurrency, Area.

Problem 927

Geometry Problem 927.
Semicircle, Diameter, Radius, Equal Arcs, Chord, Congruence.

Problem 926

Geometry Problem 926.
Two Equilateral Triangles, Midpoint, Perpendicular, Metric Relations.

Problem 925

Geometry Problem 925.
Cyclic Quadrilateral, Diagonal, Circle, Angle Bisector, Parallel.

Problem 924

Geometry Problem 924.
Quadrilateral, Diagonal, Perpendicular, Circle, Tangent, Midpoint, Metric Relations.

Problem 923

Geometry Problem 923.
Quadrilateral, Quadrangle, Obtuse Angle, Triangle, Diagonal, Inequality, Length.

Problem 922

Geometry Problem 922.
Circle, Tangent Lines, Tangency Points, Chord, Secant, Harmonic Mean.

Problem 921

Geometry Problem 921.
Right Triangle, Circumcircle, Arc, Midpoint, Tangency Point, Incircle.

Problem 920

Geometry Problem 920.
Triangle, Angles, 10, 20 Degrees, Congruence.

Problem 919

Geometry Problem 919.
Rhombus, Triangle, Perpendicular, 90 Degrees, Congruence.

Problem 918

Geometry Problem 918.
Triangle, Incenter, Incircle, Angle Bisector, Perpendicular, Metric Relations.

Problem 917

Geometry Problem 917.
Triangle, Congruence, Midpoints, Angle Bisector, Perpendicular.

Problem 916

Geometry Problem 916.
Cyclic Quadrilateral, Three Circles, Diameter, Congruence.

Problem 915

Geometry Problem 915.
Triangle, Intersecting Circles, Concyclic Points, Cyclic Quadrilateral.

Problem 914

Geometry Problem 914.
Triangle, Orthocenter, Angle Bisector, Parallel Lines, Midpoint.

Problem 913

Geometry Problem 913.
Right Triangle, Double Angle, Triple Angle, Metric Relations.

Problem 912

Geometry Problem 912.
Right Triangle, Double Angle, Triple Angle, Perpendicular Lines.

Problem 911

Geometry Problem 911.
Right Triangle, Double Angle, Triple Angle, Concyclic Points, Cyclic Quadrilateral.

Problem 910

Geometry Problem 910.
Bicentric Quadrilateral, Distance between the Incenter and Circumcenter, Incircle, Circumcircle, Circumscribed, Inscribed, Circumradius.

Problem 909 Bicentric Quadrilateral, Incircle, Circumcircle, Circumscribed, Inscribed, Tangent, Inradius

Geometry Problem 909.
Bicentric Quadrilateral, Incircle, Circumcircle, Circumscribed, Inscribed, Tangent, Inradius, Distance.

Problem 908 Bicentric Quadrilateral, Incircle, Circumcircle, Circumscribed, Inscribed, Tangent, Inradius

Geometry Problem 908.
Bicentric Quadrilateral, Incircle, Circumcircle, Circumscribed, Inscribed, Tangent, Inradius.

Problem 907 Bicentric Quadrilateral, Incircle, Circumcircle, Circumscribed, Inscribed, Tangent, Inradius

Geometry Problem 907.
Bicentric Quadrilateral, Incircle, Circumcircle, Circumscribed, Inscribed, Tangent, Inradius.

Problem 906 Bicentric Quadrilateral, Incircle, Circumcircle, Circumscribed, Inscribed, Perpendicular

Geometry Problem 906.
Bicentric Quadrilateral, Incircle, Circumcircle, Circumscribed, Inscribed, Perpendicular.

Lester Circle Theorem

Geometry Problem 905: Lester Circle Theorem.

Second Fermat Point

Geometry Problem 904: Second Fermat Point: Static diagram.
Second Fermat Point: Dynamic diagram.
Triangle, Equilateral triangles, Concurrent lines, GeoGebra, HTML5 Animation for Tablets (iPad, Nexus)

Fermat Point

Geometry Problem 903: First Fermat Point.
 

Geometry problems 881-890

Geometry Problems 881 - 890.
Triangle, Circle, Parallelogram, Trapezoid, Congruence, Similarity, Metric Relations, Incircle, Rectangle, Square

Geometry Problem 902

Static Diagram of problem 902
Dynamic Geometry Problem 902
Triangle, Four Squares, Center, Concurrent Lines. GeoGebra, HTML5 Animation for Tablets

Geometry Problem 901

Static Diagram of problem 901
Dynamic Geometry Problem 901
Intersecting Circles, Common External Tangent, Secant, Circumcircle, Concyclic Points, Cyclic Quadrilateral. GeoGebra, HTML5 Animation for Tablets

Geometry Problem 900

Geometry Problem 900
Intersecting Circles, Common External Tangent, Secant, Angle, Congruence.
GeoGebra, HTML5 Animation for Tablets

Geometry Problem 899

Geometry Problem 899
Intersecting Circles, Common External Tangent, Secant, Concyclic Points, Cyclic Quadrilateral. GeoGebra, HTML5 Animation for Tablets

Geometry Problem 898

Geometry Problem 898
Intersecting Circles, Common External Tangent, Secant, Circumcenter, Collinear Points.
GeoGebra, HTML5 Animation for Tablets

Geometry Problem 897

Geometry Problem 897
Intersecting Circles, Common External Tangent, Secant, Congruence.
GeoGebra, HTML5 Animation for Tablets

Geometry Problem 896

Geometry Problem 896
Triangle, Orthocenter, Midpoint, Median, Intersecting Circles, Diameter, Collinear Points.
GeoGebra, HTML5 Animation for Tablets

Geometry Problem 895

Geometry Problem 895
Triangle, Incircle, Tangency Points, Parallel line, Collinear Points.
GeoGebra, HTML5 Animation for Tablets

Geometry Problem 894

Geometry Problem 894
Triangle, Angle, 60 degrees, Incenter, Midpoint, Parallel Lines.
GeoGebra, HTML5 Animation for Tablets

Geometry Problem 893

Geometry Problem 893
Triangle, Circumcircle, Incenter, Circle, Tangent, Collinear Points.
GeoGebra, HTML5 Animation for Tablets

Geometry Problem 892

Geometry Problem 892
Triangle, 60 degrees, Orthocenter, Circumcenter.

Geometry Problem 891

Geometry Problem 891
Equiangular Octagon, Metric Relations, Sides, Auxiliary Lines.

Geometry Problem 890

Geometry Problem 890
Two Squares inscribed in Circles, Concurrent Lines. GeoGebra, HTML5 Animation for Tablets.

Geometry Problem 889

Geometry Problem 889
Carnot's Theorem in an acute triangle, Circumcenter, Circumradius, Inradius. GeoGebra, HTML5 Animation for Tablets.

Geometry problems 871-880

Geometry Problems 871 - 880.
Triangle, Circle, Parallelogram, Trapezoid, Congruence, Similarity, Metric Relations, Incircle, Rectangle, Square

Problem 888

Geometry Problem 888
Butterfly Theorem, Circle, Chord, Midpoint. GeoGebra, HTML5 Animation for Tablets.

Problem 887

Geometry Problem 887
Triangle, Altitude, Angle Bisector, Perpendicular, Midpoint, Concyclic Points. GeoGebra, HTML5 Animation for Tablets.

Problem 886

Geometry Problem 886
Right Triangle, Incenter, Angle Bisector, Perpendicular, 45 Degrees, Concyclic Points, Isosceles Right Triangle. GeoGebra, HTML5 Animation for Tablets (iPad, Nexus)..

Pythagoras curiosity. Online tutoring.

Geometry Problem 885
Intersecting Circles, Three Tangent Lines, Midpoint.

Pythagoras curiosity. Online tutoring.

Geometry Problem 884: The Pythagorean Curiosity
Right Triangles and squares, fifteen conclusions.

Geometry Problem 883

Geometry Problem 883
Five Circumscribed Quadrilaterals, Circle, Tangent, Common Tangent.

Geometry Problem 882

Geometry Problem 882
Triangle, Angle x, 2x, 7x, Cevian, Congruence, Auxiliary Lines.

Geometry Problem 881

Geometry Problem 881
Triangle, three Squares, Centers, Areas.

Geometry Problem 880

Geometry Problem 880
Triangle, Midpoints, Sides, Perpendiculars, Hexagon, Area.

Geometry Problem 879

Geometry Problem 879
Square, Midpoint, Diagonal, Ratio 3:1, Angle Measure.

Geometry Problem 877

Geometry Problem 878
Square, Inscribed Circle, Quadrant, Center, Perpendicular, Metric Relations.

Geometry Problem 877

Geometry Problem 877
Square, Right Triangle, Similarity, Metric Relations, Transversal.

Geometry Problem 876

Geometry Problem 876
Equilateral Triangle, any Point, Perpendicular, Right Triangle Area, Sum of Areas.

Geometry Problem 875

Geometry Problem 875
Congruent Circles, Intersecting Circles, Secant, Center, Angle Trisection, Triple Angle.

Geometry Problem 874

Geometry Problem 874
Isosceles Triangle, Circumcircle, Circumcenter, Congruence.

Geometry Problem 873: Quadrilateral, Diagonal, Triangle, Angle Bisector, Congruence

Geometry Problem 873
Quadrilateral, Diagonal, Triangle, Angle Bisector, Congruence.

Geometry Problem 872: Quadrilateral, Triangle, Angle, 30, 90 degrees

Geometry Problem 872
Quadrilateral, Triangle, Angle, 30, 90 degrees.

Cyclic Quadrilateral with perpendicular diagonals Index

Cyclic Quadrilateral with Perpendicular Diagonals.

Geometry Problem 871: Brahmagupta's Theorem, Cyclic Quadrilateral, Perpendicular Diagonals, Midpoint

Geometry Problem 871
Brahmagupta's Theorem, Cyclic Quadrilateral, Perpendicular Diagonals, Midpoint.

Geometry Problem 870: Triangle, Median, Three Squares, Centers, Vertices, Collinear Points, Midpoint

Geometry Problem 870
Triangle, Median, Three Squares, Centers, Vertices, Collinear Points, Midpoint.

Geometry Problem 869: Triangle, Median, Three Equilateral Triangles, Collinear Points, Midpoint

Geometry Problem 869
Triangle, Median, Three Equilateral Triangles, Collinear Points, Midpoint.

Geometry problem 868, Cyclic Quadrilateral, Circle, Five Rectangles, Four Centers, Congruence

Geometry Problem 868
Cyclic Quadrilateral, Circle, Five Rectangles, Four Centers, Congruence.

Dynamic Geometry: Internal Feuerbach Point. HTML5 Animation for Tablets iPad, Nexus

GeoGebra, Dynamic Geometry: Internal Feuerbach Point
HTML5 Animation for Tablets (iPad, Nexus..)

Geometry problem 867, Isosceles Triangle, Median, Perpendicular, Angle, Congruence

Geometry Problem 867
Isosceles Triangle, Median, Perpendicular, Angle, Congruence.

Geometry problem 866, Cyclic Quadrilateral, Circle, Rectangle, Center, Congruence, 90 Degrees

Geometry Problem 866
Cyclic Quadrilateral, Circle, Rectangle, Center, Congruence, 90 Degrees.

Geometry problem 865, Parallelogram, Midpoint, Parallel

Geometry Problem 865
Parallelogram, Diagonal, Midpoint, Side, Triangle, Parallel, Similarity.

Geometry problem 854 about Parallelogram

Geometry Problem 864
Parallelogram, Diagonal, Congruence, Similarity, Metric Relations.

Dynamic Geometry: Nine Point Circle. HTML5 Animation for Tablets (iPad, Nexus..)

GeoGebra, Dynamic Geometry: Nine Point Circle
HTML5 Animation for Tablets (iPad, Nexus..)

Dynamic Geometry: Lemoine Line of a Triangle. HTML5 Animation for Tablets (iPad, Nexus..)

GeoGebra, Dynamic Geometry: Lemoine Line of a Triangle.
HTML5 Animation for Tablets (iPad, Nexus..)

Dynamic Geometry: Simson Line of a Triangle. HTML5 Animation for Tablets (iPad, Nexus..)

GeoGebra, Dynamic Geometry: Simson Line of a Triangle.
HTML5 Animation for Tablets (iPad, Nexus..)

Dynamic Geometry: Euler Line of a Triangle. HTML5 Animation for Tablets (iPad, Nexus..)

GeoGebra, Dynamic Geometry: Euler Line of a Triangle.
HTML5 Animation for Tablets (iPad, Nexus..)

Circumscribed trapezoid, Inscribed Circle, Tangent

Geometry Problem 863
Circumscribed trapezoid, Inscribed Circle, Tangent, Metric Relations.

Trapezoid, Parallel, Equal Areas, RMS, Root Mean Square

Geometry Problem 862:
Trapezoid, Parallel, Equal Areas, RMS, Root Mean Square
.

GeoGebra Constructions Index

GeoGebra Constructions Index
HTML5 Animation for Tablets (iPad, Nexus..)

Triangle, Incircle, Parallel, Tangent, Metric Relations

Geometry Problem 861
Triangle, Incircle, Parallel, Tangent, Metric Relations.

Dynamic Geometry: Circumcenter and Circumcircle of a Triangle. HTML5 Animation for Tablets (iPad, Nexus..)

GeoGebra, Dynamic Geometry: Circumcenter and Circumcircle of a Triangle.
HTML5 Animation for Tablets (iPad, Nexus..)

Dynamic Geometry: Centroid of a Triangle. HTML5 Animation for Tablets (iPad, Nexus..)

GeoGebra, Dynamic Geometry: Centroid of a Triangle.
HTML5 Animation for Tablets (iPad, Nexus..)

Dynamic Geometry: Incenter and Incircle of a Triangle. HTML5 Animation for Tablets (iPad, Nexus..)

GeoGebra, Dynamic Geometry: Incenter and Incircle of a Triangle.
HTML5 Animation for Tablets (iPad, Nexus..)

Root Mean Square in Geometry

Root Mean Square (RMS) in Geometry Index

.

Geometry Art Problems

Geometry Art Problems for Desktops, High-end mobile devices and Tablets (iPad, Nexus)
Visual Index.

Dynamic Geometry: Orthocenter of a Triangle. HTML5 Animation for Tablets (iPad, Nexus..)

GeoGebra, Dynamic Geometry: Orthocenter of a Triangle.
HTML5 Animation for Tablets (iPad, Nexus..)

Triangle, Three Medians, Parallel, Parallelogram, Area, Congruence

Geometry Problem 860
Triangle, Three Medians, Parallel, Parallelogram, Area, Congruence.

Nine-point-circle, Euler Line, HTML5 Animation for iPad and Nexus

Nine-Point Center, Nine-Point Circle, Euler Line. Interactive illustration.
Circumcenter, Centroid, Orthocenter
HTML5 Animation for iPad and Nexus

Lemoine Line Theorem

Lemoine Line Theorem, Interactive illustration.
HTML5 Animation for iPad and Nexus

Isosceles Right Triangle, Angles,18, 45 Degrees, Congruence, Perpendicular bisector

Geometry Problem 859
Isosceles Right Triangle, Angles,18, 45 Degrees, Congruence, Perpendicular bisector.

Gergonne Point Theorem

Gergonne Point Theorem. Concurrency. Interactive proof with animation.
HTML5 Animation for Tablets (iPad, Nexus)
Adobe Flash Animation

Isosceles Right Triangle, Cevian, Ratio 2:1, 45 Degrees, Congruence, Angles, Auxiliary Lines

Geometry Problem 858
Isosceles Right Triangle, Cevian, Ratio 2:1, 45 Degrees, Congruence, Angles, Auxiliary Lines.

Problem 856: Triangle, Median, Midpoint, Angles, 30, 45 Degrees, Congruence, Auxiliary Lines

Geometry Problem 857
Triangle, Median, Midpoint, Angles, 30, 45 Degrees, Congruence, Auxiliary Lines.

Problem 856: Quadrilateral, Diagonals, Triangle, Angles, 30 degrees, Congruence, Auxiliary lines

Geometry Problem 856
Quadrilateral, Diagonals, Triangle, Angles, 30 degrees, Congruence, Auxiliary lines.

Platonic Solids, Interactive animation.
HTML5 Animation for iPad and Nexus

Johnson: Intersecting circles

Johnson's Theorem, Intersecting circles.
HTML5 Animation

Problem 855: Quadrilateral, Triangle, Angles, 30 degrees, Congruence, Auxiliary lines

Geometry Problem 855
Quadrilateral, Triangle, Angles, 30 degrees, Congruence, Auxiliary lines.

Problem 854: Triangle, Parallel lines, Parallelogram, Areas, Similarity, Concurrent lines

Geometry Problem 854
Triangle, Parallel lines, Parallelogram, Areas, Similarity, Concurrent lines.

Problem 853: Square, Arc, Quadrant, Triangle, Perpendicular, Metric Relations

Geometry Problem 853
Square, Arc, Quadrant, Triangle, Perpendicular, Metric Relations.

Problem 852: Triangle, Incircle, Inradius, Tangent, Metric Relations

Geometry Problem 852
Triangle, Incircle, Inradius, Tangent, Metric Relations.

Problem 851: Triangle, Triple side, Angles, 90 Degrees. Special Right triangle

Geometry Problem 851
Triangle, Triple side, Angles, 90 Degrees, Special Right triangle, Sides ratio 1:3.

Problem 850: Triangle, Double side, Angles, 90 Degrees. Special Right triangle

Geometry Problem 850
Triangle, Double side, Angles, 90 Degrees. Special Right triangle.

Special Right triangle, Catheti or legs ratio 1:3, 18.5 Degrees. Double angle

Geometry Problem 849
Special Right triangle, Catheti or legs ratio 1:3, 18.5 Degrees. Double angle.

Special Right triangle, Catheti or legs ratio 1:2, 26.5 Degrees. Double angle

Geometry Problem 848
Special Right triangle, Catheti or legs ratio 1:2, 26.5 Degrees. Double angle.

iPad Apps IGS Apollonius: Feuerbach Point. Triangle, Incircle, Nine point circle, Tangent circles, Orthocenter, Midpoint 

iPad Apps: Apollonius Software. Feuerbach Point. Triangle, Incircle, Nine point circle, Tangent circles, Orthocenter, Midpoint.
Interactive Geometry Software for iPad.

iPad Apps: Geometry Designer Geometry Software

Geometry Designer for iPad, iPhone, iPod - Index
Dynamic Geometry.

van Lamoen Circle, Triangle, Medians, Centroid, Six Circumcenters, Concyclic Points

Geometry Problem 847
van Lamoen Circle, Triangle, Medians, Centroid, Six Circumcenters, Concyclic Points.

iPad Apps IGS Geometry Designer Illustration: Circle of van Lamoen 

iPad Apps, Geometry Designer Illustration. Circle of van Lamoen.
Interactive Geometry Software for iPad, iPhone, iPod.

iPad App Geometry Designer Four Circles Theorem

iPad Apps: Geometry Designer Illustration. Four Circles Theorem.
Interactive Geometry Software for iPad, iPhone, iPod.

Triangle, Medians, Centroid, Four Circumcenters, Concyclic Points, Cyclic Quadrilateral, Similarity

Geometry Problem 846
Triangle, Medians, Centroid, Four Circumcenters, Concyclic Points, Cyclic Quadrilateral, Similarity.

Triangle, Medians, Centroid, Four Circumcenters, Perpendicular, Congruence, Similarity

Geometry Problem 845
Triangle, Medians, Centroid, Four Circumcenters, Perpendicular, Congruence, Similarity.

Triangle, Medians, Centroid, Four Circumcenters, Perpendicular, Congruence, Similarity

Geometry Problem 844
Triangle, Medians, Centroid, Four Circumcenters, Perpendicular, Congruence, Similarity.

Triangle, Medians, Centroid, Four Circumcenters, Perpendicular, Parallel, Congruence, Similarity

Geometry Problem 843
Triangle, Medians, Centroid, Four Circumcenters, Perpendicular, Parallel, Congruence, Similarity.

Triangle, Medians, Centroid, Four Circumcenters, Perpendicular, Congruence, Similarity

Geometry Problem 842
Triangle, Medians, Centroid, Four Circumcenters, Perpendicular, Congruence, Similarity.

Triangle, Medians, Centroid, Circumcenters, Perpendicular, Congruence, Similarity

Geometry Problem 841
Triangle, Medians, Centroid, Circumcenters, Perpendicular, Congruence, Similarity.

van Lamoen Circle Index

van Lamoen Circle - Index.

Parallelogram, Perpendicular, Diagonal, Metric Relations, Similarity

Geometry Problem 840
Parallelogram, Perpendicular, Diagonal, Metric Relations, Similarity.

Problem 839: Parallelogram, Perpendicular, Diagonal, Metric Relations

Geometry Problem 839
Problem 839: Parallelogram, Perpendicular, Diagonal, Metric Relations.

Parallelogram, Perpendicular, Diagonal, Metric Relations

Geometry Problem 838
Parallelogram, Perpendicular, Diagonal, Metric Relations.

Triangle, Orthocenter, Circumcenter, Circle, Concyclic Points

Geometry Problem 837
Triangle, Orthocenter, Circumcenter, Circle, Concyclic Points.

Parallelogram, Perpendicular, Diagonal, Similarity, Metric Relations

Geometry Problem 836
Parallelogram, Perpendicular, Diagonal, Similarity, Metric Relations.

Isosceles Triangle, Double Angle, Triple Angle, Auxiliary Lines

Geometry Problem 835
Isosceles Triangle, Double Angle, Triple Angle, Auxiliary Lines.

Prezi Presentation: A Geometry Course by Mark Vasicek

Prezi Presentation: A Geometry Course by Mark Vasicek
 

Parallelogram, Diagonal, Similarity, Geometric Mean, Mean Proportional

Geometry Problem 834
Parallelogram, Diagonal, Similarity, Geometric Mean, Mean Proportional.

Mean in Geometry, Index

Mean in Geometry.
Index.

Parallelogram, Diagonal, Similarity, Proportion

Geometry Problem 833
Parallelogram, Diagonal, Similarity, Proportion.

Quadrilateral, Isosceles triangle, 70-70-40 degrees, Congruence

Geometry Problem 832
Quadrilateral, Isosceles triangle, 70-70-40 degrees, Congruence, Auxiliary lines, Equilateral triangle.

Quadrilateral, Triangle, Angles, 30 degrees, Congruence

Geometry Problem 831
Quadrilateral, Diagonal, Midpoint, Opposite Angles, Congruence, Parallelogram.

Quadrilateral, Triangle, Angles, 30 degrees, Congruence

Geometry Problem 830
Quadrilateral, Triangle, Angles, 30 degrees, Congruence.

Triangle, Circumcircle, Parallel, Chord, Side, Metric Relations

Geometry Problem 829
Triangle, Circumcircle, Parallel, Chord, Side, Metric Relations.

Geometry Problem Quadrilateral Midpoint

Geometry Problem 828
Quadrilateral, Midpoint, Opposite sides, Diagonals, Concurrent lines, Triangle, Bimedian.

Semicircle, Chord, Arc, Area

Geometry Problem 827: Brianchon Corollary
Circumscribed Hexagon, Tangency Points, Diagonal, Opposite Sides, Concurrent lines.

Brianchon's Theorem, Circumscribed Hexagon, Concurrent Diagonals

Geometry Problem 826: Brianchon's Theorem
Circumscribed Hexagon, Concurrent Diagonals.

Semicircle, Chord, Arc, Area

Geometry Problem 825.
Circle, Semicircle, Arc, Chord, Midpoint, Sector, Triangle, Area.

Desargues' Theorem, Triangles in Perspective

Geometry Problem 824
Desargues' Theorem, Triangles in Perspective.

Tangent Circles, Diameter, Perpendicular, Triangle, Area, Tangency Point

Geometry Problem 823.
Tangent Circles, Diameter, Perpendicular, Chord, Secant, Triangle, Area, Tangency Point.

Area of a Circle

Circle Area. Index.
Theorems and Problems. 
 

Semicircle, Chord, Arc, Area

Geometry Problem 822.
Circle, Semicircle, Arc, Chord, Midpoint, Sector, Triangle, Area.

Adams Circle

Geometry Problem 821.
Adams Circle.

Triangle, Angles, 30 Degrees

Geometry Problem 820.
Triangle, Cevian, Angles, 30 Degrees.

Geometry problems 811-820

Geometry Problems 811 - 820.
Triangle, Circle, Quadrilateral, Square, Pitot Theorem, Arbelos, Tangent, 30 Degrees.

Quadrilateral, Triangle, Angles

Geometry Problem 819.
Quadrilateral, Triangle, Angles, 30 degrees.

Square, Triangle, Angle

Geometry Problem 818.
Square, Triangle, Angle.

Two Circles, Tangent Lines

Geometry Problem 817.
Two circles, Tangent Lines, Circumscribed Quadrilaterals.

Tangential Quadrilateral: Pitot Theorem

Geometry Problem 816.
Tangential or Circumscribed Quadrilateral: Pitot Theorem.

Triangle, Incircle, Arbelos, Area

Geometry Problem 815.
Triangle, Incircle, Semicircles, Arbelos, Area.

Equilateral triangles, a common vertex

Geometry Problem 814.
Two Equilateral Triangles with a common Vertex, Angle.

Right triangle, Excircles, Area

Geometry Problem 813.
Right Triangle Area, Excircles, Cathetus, Tangency Points, Quadrilateral Area.

Circle Area, Tangent 

Geometry Problem 812.
Four Tangent Circles, Common Tangent Line, Diameter, Area, Collinear Centers.

Trisecting a line segment, 4 circles

Geometry Problem 811: Trisecting a line segment.
With four circles and one line.

Trisecting a line segment, 2 circles

Geometry Problem 810: Trisecting a line segment.
With two circles and eight lines.

Trisecting a segment with three circles

Geometry Problem 809: Trisecting a line segment.
With three circles and four lines.

Parallelogram, Perpendicular, Semicircle, Area

Geometry Problem 808
Parallelogram, Perpendicular, Right Triangle, Semicircle Area, Diameter.

Right Triangle Area, Incircle, Semicircle

Geometry Problem 807
Right Triangle Area, Incircle, Tangency Points, Semicircle Area.

Lines, Theorems and  Problems Index

Lines. Theorems and Problems.

Trisecting a Line Segment Theorems and Problems

Trisecting a Line Segment.
Theorems and Problems

Triangle, Circumcenter, Similarity

Geometry Problem 806
Triangle, Points on sides, Circumcenter, Similarity.

Area of a Right Triangle, Theorems and Problems

Area of a Right Triangle, Theorems and Problems.

iPad Apps IGS Apollonius: Right triangle, altitude, incenters 

iPad Apps: Apollonius Software. Problem 794: Right Triangle, Altitude, Three Incenters, Circumcircles, Incircle, Congruence.
Interactive Geometry Software.

Stewart Theorem

Geometry Problem 805, Stewart Theorem
Triangle, sides and a cevian.

iPad Apps: Apollonius Geometry Software

iPad Apps: Apollonius, Interactive Geometry Software IGS Index.
Theorems and Problems with Apollonius for iPad.

Butterfly theorem

Geometry Problem 804
Circle, Chord, Midpoints.

Right Triangle, Altitude, Angle Bisector, Perpendicular, Measurement

Geometry Problem 803
Right Triangle, Altitude, Angle Bisector, Perpendicular, Measurement.

iPad Geoboard: Pythagorean Theorem proof by Leonardo 

Geoboard for iPad Pythagorean Theorem Proof by Leonardo.

Polygon definition

Polygon definition

Geoboard: Squares, midpoints of sides

Geoboard for iPad Gallery: Squares inscribed in squares.
Midpoints of the sides, Sequence, Recursive Form, Areas

iPadd Apps Geoboard, triangle with two squares

Geoboard for iPad Gallery: Triangle with two squares (Problem 496).

iPad Geoboard: Six squares with a common vertex 

Geoboard for iPad Gallery: Six squares with a common vertex.

Triangle definition

Triangle definition

Geoboard for iPad Index

Geoboard for iPad Index.
This virtual version is an open-ended educational tool, ideal for elementary classrooms and other learning environments that use iPod Touches, iPhones, or iPads

iPad Geoboard: Pythagorean Theorem proof 

Geoboard for iPad Pythagorean Theorem Proof, Squares (Problem 540).

Scalene Triangle, Median, Perpendicular, Angle, Measurement

Geometry Problem 802
Scalene Triangle, Median, Perpendicular, Angle, Measurement.

Equilateral Triangles, Midpoint

Geometry Problem 801
Equilateral Triangles, Cevian, Midpoint, Distance, Measurement, Metric Relations.

de Gua's theorem

Geometry Problem 800: de Gua's Theorem
Pythagorean theorem in 3-D, Tetrahedron, Cubic Vertex, Triangular Pyramid, Apex, Height, Right Triangle Area, Base Area, Projected Area.

Parallelogram, Angle Bisector, Parallel, Triangle, Circumcircle, Circumcenter

Geometry Problem 799
Parallelogram, Angle Bisector, Parallel, Triangle, Circumcircle, Circumcenter.

Parallelogram, Secant Line, Tangent Circles, Triangle

Geometry Problem 798
Parallelogram, Secant Line, Tangent Circles, Circumcircles, Triangle.

Parallelogram, Angle Bisector

Geometry Problem 797
Parallelogram, Angle Bisector, Isosceles and Similar Triangles.

Triangle, Altitude, Angle

Geometry Problem 796
Triangle, Altitude, Measurement of Angles.

Right Triangle, Altitude, Incircles, CIrcumcircles, COngruence

Geometry Problem 795
Intersecting Circles, Common Chord, Midpoint, Tangent, Secant Line, Perpendicular, 90 Degrees.

Right Triangle, Altitude, Incircles, CIrcumcircles, COngruence

Geometry Problem 794
Right Triangle, Altitude, Three Incenters, Circumcircles, Incircle, Congruence.

Right Triangle, Altitude, Three Incircles, Circumradius

Geometry Problem 793
Right Triangle, Altitude, Three Incircles, Incenters, Circumcircle, Circumradius, Perpendicular, Distance.

Right Triangle, Altitude, Angle Bisector, Three Incircles, Five Concyclic Points, Circles

Geometry Problem 792
Right Triangle, Altitude, Angle Bisector, Three Incircles, Five Concyclic Points, Circles.

Regular Hexagon, Midpoints, Equilateral Triangle

Geometry Problem 791
Regular Hexagon, Midpoints of Side and Diagonal, Equilateral Triangle, Area.

Right Triangle, Altitude, Incenter, Angle Bisector, Inradius

Geometry Problem 790
Right Triangle, Altitude, Angle Bisector, Incircle, Tangency Point, Inradius, Circles, Tangent Line, Congruence.

Right Triangle, Altitude, Angle Bisector, Inradius

Geometry Problem 789
Right Triangle, Altitude, Angle Bisector, Incircle, Tangency Point, Inradius, Circles, Tangent Line.

Intersecting Circles, Secant Line, Midpoint, Cyclic Quadrilateral

Geometry Problem 788
Intersecting Circles, Secant Line, Midpoint, Cyclic Quadrilateral.

Right Triangle, Altitude, Incircle Index

Right triangle, Altitude, Incircle
Right Triangle, Altitude to the Hypotenuse, Incircle, Incenter, Inradius, Angle Bisector, Theorems and Problems, Index.

Right Triangle, Inradius, 18 Equal Circles, Line Tangent, Legs, Hypotenuse, Ratio, Metric Relations

Geometry Problem 787
Right Triangle, Inradius, 18 Equal Circles, Line Tangent, Legs, Hypotenuse, Ratio, Metric Relations.

Right Triangle, Altitude, Hypotenuse, Cevian, Perpendicular, Ratio

Geometry Problem 786
Right Triangle, Altitude, Hypotenuse, Cevian, Perpendicular, Ratio, Metric relations.

Equilateral Triangle, Parallel, Perpendicular

Geometry Problem 785
Equilateral Triangle, Parallel, Perpendicular.

Triangle, Orthocenter, Midpoint

Geometry Problem 784
Triangle, Orthocenter, Altitude, Midpoint of a side, Perpendicular.

Triangle, Orthocenter, Circumcircle, Diameter, Midpoint

Geometry Problem 783
Triangle, Orthocenter, Circumcenter, Circumcircle, Diameter, Altitude, Midpoint.

Triangle, Orthocenter, Circumcircle, Diameter, Altitude, Parallelogram

Geometry Problem 782
Triangle, Orthocenter, Circumcenter, Circumcircle, Diameter, Altitude, Parallelogram.

Triangle, Orthocenter, Circumcenter, Vertex, Altitude, Midpoint, Perpendicular

Geometry Problem 781
Triangle, Orthocenter, Circumcenter, Vertex, Altitude, Midpoint, Perpendicular.

Isogonal Lines

Isogonal Lines.
Theorems and Problems.

Go to Page: Previous | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | Next

 

 

 

Home | SearchGeometry | Email | By Antonio Gutierrez