Useful Links
Mathematics
Geometry
1. Foundations of Euclidean Geometry
2. Angles
3. Parallel and Perpendicular Lines
4. Logic and Geometric Proofs
5. Triangles
6. Right Triangles and Trigonometry
7. Similarity
8. Quadrilaterals and Polygons
9. Circles
10. Geometric Transformations
11. Three-Dimensional Geometry
12. Coordinate Geometry
Circles
Circle Fundamentals
Definition of a Circle
Center and Radius
Diameter
Relationship Between Radius and Diameter
Circle Notation
Congruent Circles
Concentric Circles
Lines and Segments Related to Circles
Chord
Definition and Properties
Perpendicular Bisector of a Chord
Distance from Center to Chord
Secant
Definition and Properties
Secant Segments
Tangent
Definition and Properties
Point of Tangency
Tangent Segments from External Point
Perpendicular to Radius at Point of Tangency
Arcs and Central Angles
Central Angles
Definition and Measurement
Relationship to Intercepted Arc
Arcs
Minor Arc
Major Arc
Semicircle
Arc Measure
Relationship to Central Angle
Arc Addition Postulate
Congruent Arcs
Inscribed Angles and Polygons
Inscribed Angles
Definition and Properties
Inscribed Angle Theorem
Inscribed Angles Intercepting Same Arc
Angles Formed by Chords
Intersecting Chords Angle Theorem
Angles Formed by Secants and Tangents
External Angle Theorems
Tangent-Chord Angles
Circle Measurements
Circumference
Circumference Formula
Relationship to Diameter and Radius
Pi as a Constant
Arc Length
Arc Length Formula
Relationship to Central Angle
Area of a Circle
Area Formula
Derivation of Formula
Area of Sectors
Sector Definition
Sector Area Formula
Area of Segments
Segment Definition
Calculating Segment Area
Power of a Point
Intersecting Chords Theorem
Secant Segments Theorem
Tangent-Secant Theorem
Applications of Power Theorems
Equations of Circles
Standard Form Equation
Center and Radius from Equation
Graphing Circles
Writing Equations from Given Information
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8. Quadrilaterals and Polygons
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10. Geometric Transformations