Plane Geometry

Plane geometry is all about shapes like lines, circles and triangles ... shapes that can be drawn on a flat surface called a Plane (it is like on an endless piece of paper).

If you like drawing, geometry is for you!

General

Plane
Geometric Symbols
Areas
Congruent
Pythagoras' Theorem
Pythagorean Triples
Quadrilaterals - Rhombus, Parallelogram, etc
Right Angled Triangles
Shape
Similar
Triangles
Circle

Transversal

Using Drafting Tools (Ruler, Triangle, Compass)

Using the Protractor Using the Drafting Triangle and Ruler Using a Ruler and Compass

Area Calculation Tool

Transformations and Symmetry

Transformations Index
Symmetry Index
Symmetry Artist

Angles

Degrees (Angle)
Acute Angles
Right Angles
Obtuse Angles
Straight Angle
Reflex Angles
Parallel Lines and Pairs of Angles
Proof that a Triangle has 180°
Congruent Angles

Supplementary Angles
Complementary Angles

Angles Around a Point
Angles on a Straight Line

Interior Angles
Exterior Angles

Trigonometry