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Geometry begins with a handful of fundamental ideas that describe the space around us. A point is the simplest of these: it represents a single location in space but has no size, n...
An angle is formed wherever two rays share a common endpoint, called the vertex, and angles are measured in degrees based on the amount of rotation between them. The basic types de...
Triangles are among the most studied shapes in geometry, and they can be sorted in two main ways. Classified by side length, an equilateral triangle has all three sides equal, an i...
The most famous result in all of geometry applies specifically to right triangles. The Pythagorean Theorem states that in any right triangle with legs of length a and b and hypoten...
A circle is the set of all points in a plane that are the same distance, called the radius, from a central point. The distance across the circle through the center is called the di...
A regular polygon is a polygon with all sides equal in length and all interior angles equal in measure. Common examples include equilateral triangles, squares, and regular hexagons...
Coordinate geometry connects algebra and geometry by placing points on a grid. The distance between two points (x₁, y₁) and (x₂, y₂) is given by d = √[(x₂ − x₁)² + (y₂ − y₁)²], a f...