Theorem eqtr3i

Description: An equality transitivity inference. (Contributed by NM, 6-May-1994)

	Ref	Expression
Hypotheses	eqtr3i.1	$$⊢A=B$$
	eqtr3i.2	$$⊢A=C$$
Assertion	eqtr3i	$$⊢B=C$$

Proof

Step	Hyp	Ref	Expression
1		eqtr3i.1	$$⊢A=B$$
2		eqtr3i.2	$$⊢A=C$$
3	1	eqcomi	$$⊢B=A$$
4	3 2	eqtri	$$⊢B=C$$