Metamath Proof Explorer


Theorem opeq12

Description: Equality theorem for ordered pairs. (Contributed by NM, 28-May-1995)

Ref Expression
Assertion opeq12 ( ( 𝐴 = 𝐶𝐵 = 𝐷 ) → ⟨ 𝐴 , 𝐵 ⟩ = ⟨ 𝐶 , 𝐷 ⟩ )

Proof

Step Hyp Ref Expression
1 opeq1 ( 𝐴 = 𝐶 → ⟨ 𝐴 , 𝐵 ⟩ = ⟨ 𝐶 , 𝐵 ⟩ )
2 opeq2 ( 𝐵 = 𝐷 → ⟨ 𝐶 , 𝐵 ⟩ = ⟨ 𝐶 , 𝐷 ⟩ )
3 1 2 sylan9eq ( ( 𝐴 = 𝐶𝐵 = 𝐷 ) → ⟨ 𝐴 , 𝐵 ⟩ = ⟨ 𝐶 , 𝐷 ⟩ )