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Metamath Proof Explorer

Theorem equtr

Description: A transitive law for equality. (Contributed by NM, 23-Aug-1993)

		Ref	Expression
	Assertion	equtr	$⊢ x = y \to (y = z \to x = z)$

Step	Hyp	Ref	Expression
1		ax7	$⊢ y = x \to (y = z \to x = z)$
2	1	equcoms	$⊢ x = y \to (y = z \to x = z)$