
Distance Formula Geometry: Derivation, Examples, and Mistakes
The distance formula gives the straight-line distance between two points on a coordinate plane. For points (x₁, y₁) and (x₂, y₂), d = √((x₂ − x₁)² + (y₂ − y₁)²). It extends the Pythagorean theorem: the two coordinate differences form the legs of a right triangle, and d is the hypotenuse, which is the length of segment AB. Label the two points, subtract matching coordinates, square and add, then take the principal square root to find the segment length.




