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Take a guided, problem-solving based approach to learning Geometry. These compilations provide unique perspectives and applications you won't find anywhere else.

Geometry Fundamentals

What's inside
  • Introduction
  • Angles and Lengths
  • Area
  • Pythagoras' Geometry
  • Scaling and Volume
  • When Geometry Gets Tough

Beautiful Geometry

What's inside
  • Introduction
  • Tessellations and Reptiles
  • Polyominos
  • Folding Puzzles
  • Guarding Galleries
  • Pick's Theorem

Geometry I

What's inside
  • Introduction
  • Angles
  • Triangles
  • Composite Polygons
  • Regular Polygons
  • When Geometry Gets Tough

Additional Practice

Sharpen your skills with these quizzes designed to check your understanding of the fundamentals.

Geometric Measurement
  • Quadrilaterals

    These shapes have four sides and 360° of interior angle goodness.

  • Similar Polygons

    Similar polygons have the same shape, but not necessarily the same size. Are rectangles with dimensions 8 x 5 and 25 x 40 similar?

  • Regular Polygons

    With equal angles and equal side lengths, what more could you want from a polygon?

  • General Polygons

    Convex and concave, regular and irregular, similar and congruent – learn every variety of polygon you can encounter.

Coordinate Geometry
  • Equation of a Line

    Explore how simple equations have graphical implications starting with the equation of a line.

  • 2D Coordinate Geometry

    In the 1600s, René Descartes married algebra and geometry to create the Cartesian plane.

  • Conic Sections

    Parabolas, ellipses, and hyperbolas, oh my! Learn about this eccentric bunch of shapes.

  • 3D Coordinate Geometry

    Append a z-axis to the 2-dimensional plane and conquer the realm of 3-dimensional space.

  • Trigonometric Functions

    SOH-CAH-TOA! Have you heard the call of the trig function? Use them to navigate the trickier sides (and angles) of geometric shapes.

  • Graphs of Trigonometric Functions

    Plot the six different trig functions, discover their illuminating interactions, and ride the wave!

  • Trigonometric Equations

    Equations with trigonometry in them can look scary, but that's nothing that a quick little substitution can't fix.

  • Solving Triangles

    Trigonometric problem solving culminates in this chapter. Leave no side and no angle unmeasured!

Trigonometric Identities
3D Geometry
Euclidean Geometry
Geometric Transformations

Community Wiki

Browse through thousands of Geometry wikis written by our community of experts.


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