In geometry, two figures or objects are congruent if they have the same shape and size, or if one has the same shape and size as the mirror image of the other.
More formally, two sets of points are called congruent if, and … See more

In a Euclidean system, congruence is fundamental; it is the counterpart of equality for numbers. In analytic geometry, congruence may be … See more

Two conic sections are congruent if their eccentricities and one other distinct parameter characterizing them are equal. Their eccentricities … See more

As with plane triangles, on a sphere two triangles sharing the same sequence of angle-side-angle (ASA) are necessarily congruent (that is, they have three identical sides and … See more

For two polygons to be congruent, they must have an equal number of sides (and hence an equal number—the same number—of vertices). Two polygons with n sides are congruent … See more

Two triangles are congruent if their corresponding sides are equal in length, and their corresponding angles are equal in measure.
Symbolically, we write the congruency and incongruency of two triangles △ABC and △A′B′C′ as follows: See more

For two polyhedra with the same combinatorial type (that is, the same number E of edges, the same number of faces, and the same number of sides on corresponding … See more