Metamath Proof Explorer


Theorem opabid2

Description: A relation expressed as an ordered pair abstraction. (Contributed by NM, 11-Dec-2006)

Ref Expression
Assertion opabid2 RelAxy|xyA=A

Proof

Step Hyp Ref Expression
1 vex zV
2 vex wV
3 opeq1 x=zxy=zy
4 3 eleq1d x=zxyAzyA
5 opeq2 y=wzy=zw
6 5 eleq1d y=wzyAzwA
7 1 2 4 6 opelopab zwxy|xyAzwA
8 7 gen2 zwzwxy|xyAzwA
9 relopabv Relxy|xyA
10 eqrel Relxy|xyARelAxy|xyA=Azwzwxy|xyAzwA
11 9 10 mpan RelAxy|xyA=Azwzwxy|xyAzwA
12 8 11 mpbiri RelAxy|xyA=A