Metamath Proof Explorer


Theorem opeq12d

Description: Equality deduction for ordered pairs. (Contributed by NM, 16-Dec-2006) (Proof shortened by Andrew Salmon, 29-Jun-2011)

Ref Expression
Hypotheses opeq1d.1 φA=B
opeq12d.2 φC=D
Assertion opeq12d φAC=BD

Proof

Step Hyp Ref Expression
1 opeq1d.1 φA=B
2 opeq12d.2 φC=D
3 opeq12 A=BC=DAC=BD
4 1 2 3 syl2anc φAC=BD