congruent

Congruent shapes are the same size and the same shape. Both B and C are the same size and shape as A, so they are said to be congruent to A.

In geometry, having the same shape and size (and area), as applied to two-dimensional or solid figures. With plane congruent figures, one figure will fit on top of the other exactly, though this may first require rotation, translation, or reflection of one of the figures.

Some simple rules about congruence may be stated: two line segments are congruent if they are of equal length; two triangles are congruent if their corresponding sides are equal in length, or if two sides and an angle in one triangle are equal to the corresponding ones in the other triangle, or if two angles and one side in one triangle are equal to the corresponding ones in the other triangle; two circles are congruent if they have the same radius; two polygons are congruent if they can be divided into congruent triangles assembled in the same order.