Theorem eqbrtrrid

Description: A chained equality inference for a binary relation. (Contributed by NM, 17-Sep-2004)

	Ref	Expression
Hypotheses	eqbrtrrid.1	|- B = A
	eqbrtrrid.2	|- ( ph -> B R C )
Assertion	eqbrtrrid	|- ( ph -> A R C )

Proof

Step	Hyp	Ref	Expression
1		eqbrtrrid.1	|- B = A
2		eqbrtrrid.2	|- ( ph -> B R C )
3		eqid	|- C = C
4	2 1 3	3brtr3g	|- ( ph -> A R C )