Definition:Congruence (Geometry)/Opposite

Definition

Let $A$ and $B$ be $3$-dimensional figures which are congruent.

$A$ and $B$ are oppositely congruent if and only if $A$ and $B$ cannot be made to coincide with rotations and translations, but also need a reflection for this to happen.

Also see

• Definition:Direct Congruence

• Results about congruence in the context of geometry can be found here.

Sources

• 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): congruent: 1.
• 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): congruent: 1.