The Geometer's Warehouse

• Stage 4
  • MA4-17MG Properties of geometrical figures
    • Congruency
      • Congruent figures 1
      • Congruent figures 2
      • Congruent triangles
    • Quadrilaterals 1
      • Finding an unknown angle - Quadrilateral
      • Properties of the special quadrilaterals - Kite
      • Properties of the special quadrilaterals - Parallelogram
      • Properties of the special quadrilaterals - Rectangle
    • Quadrilaterals 2
      • Properties of the special quadrilaterals - Rhombus
      • Properties of the special quadrilaterals - Square
      • Properties of the special quadrilaterals - Trapezium
      • Symmetry
    • Similarity
      • Similar figures
    • Triangles
      • Equilateral triangles
      • Exterior angle of a triangle
      • Finding an unknown angle - Triangle
      • Isosceles triangles
      • Longest side of a triangle
      • Relationship between two sides of a triangle and the third side
  • MA4-18MG Angle relationships
    • Angles associated with transversals
      • Alternate angles on parallel lines
      • Angles formed when two lines are cut by a transversal
      • Co-interior angles on parallel lines
      • Corresponding angles on parallel lines
    • Angles at a point
      • Adjacent angles 1
      • Adjacent angles 2
      • Angles at a point
      • Vertically opposite angles
• Stage 5
  • MA5.1-11MG Properties of geometrical figures
    • Similarity
      • Similar circles
      • Similar triangles 1
      • Similar triangles 2
      • Similar triangles 3
  • MA5.2-14MG Properties of geometrical figures
    • Convex polygons
      • Angle sum of the exterior angles of a convex polygon
      • Angle sum of the interior angles of a convex polygon
    • Quadrilaterals
      • Convex and non-convex polygons
  • MA5.3-15MG Trigonometry and Pythagoras' Theorem
    • Pythagoras' Theorem
      • Pythagoras' theorem
      • Converse of Pythagoras' theorem
  • MA5.3-16MG Properties of geometrical figures
    • Quadrilaterals
      • Angle sum of the interior angles of a quadrilateral
      • Quadrilateral formed from the midpoints of a quadrilateral
      • Test for a parallelogram 1
      • Test for a parallelogram 2
      • Test for a rhombus
    • Triangles 1
      • Altitudes of the sides of a triangle
      • Angle sum of the interior angles of a triangle
      • Interval joining the midpoints of two sides of a triangle
      • Line through the midpoint parallel to another side
      • Medians of the sides of a triangle
    • Triangles 2
      • Napoleon's theorem
      • Perpendicular bisectors of the side of a triangle
      • Triangle with three equal sides
      • Triangle with two equal angles
      • Triangle with two equal sides
  • MA5.3-17MG Circle Geometry
    • Angle properties
      • Angle at the centre of a circle
      • Angle in a semicircle
      • Angles at the circumference
      • Exterior angle at the vertex of cyclic quadrilateral
      • Opposite angles of cyclic quadrilateral
    • Chord properties
      • Circle through any three non-collinear points
      • Equal chords in a circle
      • Line from centre of circle
      • Line of centres
      • Perpendicular bisector of a chord
      • Perpendicular from centre of circle
    • Tangent and secant properties
      • Angle between tangent and radius at point of contact
      • Angle in the alternate segment
      • Line of centres
      • Product of intercepts of intersecting chords
      • Product of intercepts of intersecting secants
      • Square of tangent from external point
      • Tangents to circle from external point

• Copyright
• Teacher notes