Collinear: Learn what collinear points are and

Learn what collinear points are and how to test them in geometry. Find examples, theorems, and applications of collinearity in various problems and contexts. Learn how to show that points are collinear using vectors, distance, or cross product. Find the formula for determining collinearity and examples of collinear and non-collinear points in 2D and 3D. Collinear points are three or more points that lie on the same straight line. The word ‘Collinear’ is a compound word that is made of two words: ‘co’ meaning togetherness and ‘linear’ meaning a line. Explore the formal definitions, properties, examples, and applications of collinear points in geometry with expert insights and updated explanations for 2025.