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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 