Metamath Proof Explorer


Theorem elopabr

Description: Membership in an ordered-pair class abstraction defined by a binary relation. (Contributed by AV, 16-Feb-2021) (Proof shortened by SN, 11-Dec-2024)

Ref Expression
Assertion elopabr A x y | x R y A R

Proof

Step Hyp Ref Expression
1 opabss x y | x R y R
2 1 sseli A x y | x R y A R