3.2 Geometric Thinking
Strengthen your geometric intuition and logical reasoning skills through problem solving.
Triangles and Hexagons
Strategic Geometry
Driving on a Polygon
Angle Hunting Axioms
Advanced Mental Shortcuts
Internal Angles in a Polygon
Invariant Angle Sets
Advanced Angle Hunts
The Triangle Inequality
Congruent and Similar Triangles
Bass Fishing
Curry's Paradox
Composite Figure Warm-ups
Adding Lines and Grids
Complementary Areas
Inclusion and Exclusion
Invariant Areas
Angles of Regular Polygons
Is It Regular?
Polygon Areas and Lengths
Matchstick Polygons
Stellations
Dissections
Central Angles and Arcs
Thales's Theorem
Inscribed Angles
Puzzles with Inscribed Angles
Cyclic Quadrilaterals
Power of a Point I
Intersecting Secants
Power of a Point II
Tangents
Problem-Solving Challenges
Right Triangles
Thales + Pythagoras
Cevians
Pegboard Triangles
Three Different Centers
The Circumcenter
Euler's Line
Morley's Triangle
Geometric Stumpers
Challenging Composites
Coordinate Geometry
Advanced Angle Hunting
Applying the Pythagorean Theorem
Course description
In this course, you'll solve delightful geometry puzzles and build a solid foundation of skills for problem-solving with angles, triangles, polygons, and circles. You'll learn how to come up with clever, creative solutions to tough challenges and explore a wide range of theorems. This course is the perfect place to start (or continue) your exploration of geometry if you know how to measure angles and calculate the areas of rectangles, circles, and triangles; and want to learn the next level of geometric problem-solving techniques. Additionally, this is a great course to take if you want to strengthen your geometric intuition in preparation for taking a geometry or design course in school. You'll also need to use a little bit of fundamentals-level algebra in this course, but nothing more advanced than two-variable equations, squares, and square roots.
Topics covered
- Angle Axioms
- Angle Hunting Shortcuts
- Composite Area
- Complementary Areas
- Curry's Paradox
- Invariant Areas
- Polygon Angles
- Regular Polygons
- Stellations
- The Triangle Inequality
- Triangle Congruence
- Triangle Similarity
- Centroid
- Circumcenter
- Cyclic Quadrilateral Theorem
- Euler's Line
- Incenter
- Inscribed Angles
- Intersecting Chord Theorem
- Intersecting Secants Theorem
- Intersecting Tangent Theorem
- Orthocenter
- Power of a Point Theorem
Prerequisites
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