Metamath Proof Explorer


Theorem breqi

Description: Equality inference for binary relations. (Contributed by NM, 19-Feb-2005)

Ref Expression
Hypothesis breqi.1 R = S
Assertion breqi A R B A S B

Proof

Step Hyp Ref Expression
1 breqi.1 R = S
2 breq R = S A R B A S B
3 1 2 ax-mp A R B A S B