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# geometry

Geometry notations View version details

## Geometry

 The Euclidean plane The -axis of the Euclidean plane The -axis of the Euclidean plane Points in the Euclidean plane with certain coordinates , , , etc. The line that passes through points and This says that the points , and are collinear, i.e. there exists a unique line which passes through all of them. The segment with endpoints and The length of the segment with endpoints and This says that the lines and are parallel, i.e. they do not have any points in common. This says that the lines and are perpendicular, i.e. they form a right angle at their point of intersection. The distance between the points and The distance between the point and the line The angle with vertex and rays , The triangle with vertices , and This says that the triangles and are congruent, which means that This says that the triangles and are similar, which basically means The quadrilateral with vertices , , and The area of the triangle The area of the quadrilateral The circle with center at the point and radius equal to