Metamath Proof Explorer


Theorem eqimss

Description: Equality implies inclusion. (Contributed by NM, 21-Jun-1993) (Proof shortened by Andrew Salmon, 21-Jun-2011)

Ref Expression
Assertion eqimss A = B A B

Proof

Step Hyp Ref Expression
1 eqss A = B A B B A
2 1 simplbi A = B A B