Theorem bnj1292

Description: First-order logic and set theory. (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)

	Ref	Expression
Hypothesis	bnj1292.1	$$⊢A=B\cap C$$
Assertion	bnj1292	$$⊢A\subseteq B$$

Proof

Step	Hyp	Ref	Expression
1		bnj1292.1	$$⊢A=B\cap C$$
2		inss1	$$⊢B\cap C\subseteq B$$
3	1 2	eqsstri	$$⊢A\subseteq B$$