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Metamath Proof Explorer

Theorem relssr

Description: The subset relation is a relation. (Contributed by Peter Mazsa, 1-Aug-2019)

		Ref	Expression
	Assertion	relssr	$⊢ Rel S$

Step	Hyp	Ref	Expression
1		df-ssr	$⊢ S = \{⟨x, y⟩ \| x \subseteq y\}$
2	1	relopabiv	$⊢ Rel S$