Metamath Proof Explorer


Theorem eliminable2a

Description: A theorem used to prove the base case of the Eliminability Theorem (see section comment). (Contributed by BJ, 19-Oct-2019) (Proof modification is discouraged.) (New usage is discouraged.)

Ref Expression
Assertion eliminable2a x=y|φzzxzy|φ

Proof

Step Hyp Ref Expression
1 dfcleq x=y|φzzxzy|φ